diff --git a/services/github/pod-github/src/sync/__tests__/pullrequests.test.ts b/services/github/pod-github/src/sync/__tests__/pullrequests.test.ts
new file mode 100644
index 0000000000..25f5ccf3c0
--- /dev/null
+++ b/services/github/pod-github/src/sync/__tests__/pullrequests.test.ts
@@ -0,0 +1,238 @@
+/* eslint-disable import/first */
+import { PersonId } from '@hcengineering/core'
+import { PullRequestExternalData } from '../githubTypes'
+import type { UserInfo } from '../../types'
+
+// Mock dependencies before imports
+jest.mock('@octokit/webhooks-types', () => ({}), { virtual: true })
+jest.mock('octokit', () => ({}), { virtual: true })
+jest.mock('../../config', () => ({
+  default: {
+    AccountsURL: 'http://localhost:3000',
+    ServerSecret: 'test-secret',
+    AppId: 'test-app-id',
+    ClientId: 'test-client-id',
+    ClientSecret: 'test-client-secret',
+    PrivateKey: 'test-private-key',
+    CollaboratorURL: 'http://localhost:3078',
+    BotName: 'test-bot'
+  }
+}))
+
+import { PullRequestSyncManager } from '../pullrequests'
+/* eslint-enable import/first */
+
+describe('PullRequestSyncManager', () => {
+  describe('getReviewers', () => {
+    let manager: PullRequestSyncManager
+    let mockProvider: any
+
+    beforeEach(async () => {
+      mockProvider = {
+        getAccount: jest.fn()
+      }
+      manager = new PullRequestSyncManager(null as any, null as any, null as any)
+      await manager.init(mockProvider)
+    })
+
+    it('should handle null reviewRequests gracefully', async () => {
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: null as any,
+        latestReviews: { nodes: [], totalCount: 0 }
+      }
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual([])
+      expect(mockProvider.getAccount).not.toHaveBeenCalled()
+    })
+
+    it('should handle undefined reviewRequests gracefully', async () => {
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: undefined as any,
+        latestReviews: { nodes: [], totalCount: 0 }
+      }
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual([])
+      expect(mockProvider.getAccount).not.toHaveBeenCalled()
+    })
+
+    it('should handle null items in reviewRequests.nodes', async () => {
+      const user1: UserInfo = { id: 'user1', login: 'user1' }
+      const user2: UserInfo = { id: 'user2', login: 'user2' }
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: {
+          nodes: [null, { requestedReviewer: user1 }, null, { requestedReviewer: user2 }] as any,
+          totalCount: 4
+        },
+        latestReviews: { nodes: [], totalCount: 0 }
+      }
+
+      mockProvider.getAccount.mockImplementation((user: UserInfo) => {
+        return Promise.resolve(user.id as PersonId)
+      })
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual(['user1', 'user2'])
+      expect(mockProvider.getAccount).toHaveBeenCalledTimes(2)
+    })
+
+    it('should handle null requestedReviewer in nodes', async () => {
+      const user1: UserInfo = { id: 'user1', login: 'user1' }
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: {
+          nodes: [{ requestedReviewer: null }, { requestedReviewer: user1 }, { requestedReviewer: null }] as any,
+          totalCount: 3
+        },
+        latestReviews: { nodes: [], totalCount: 0 }
+      }
+
+      mockProvider.getAccount.mockImplementation((user: UserInfo) => {
+        return Promise.resolve(user.id as PersonId)
+      })
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual(['user1'])
+      expect(mockProvider.getAccount).toHaveBeenCalledTimes(1)
+    })
+
+    it('should filter out reviewers when getAccount returns undefined', async () => {
+      const user1: UserInfo = { id: 'user1', login: 'user1' }
+      const user2: UserInfo = { id: 'user2', login: 'user2' }
+      const user3: UserInfo = { id: 'user3', login: 'user3' }
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: {
+          nodes: [{ requestedReviewer: user1 }, { requestedReviewer: user2 }, { requestedReviewer: user3 }] as any,
+          totalCount: 3
+        },
+        latestReviews: { nodes: [], totalCount: 0 }
+      }
+
+      mockProvider.getAccount.mockImplementation((user: UserInfo) => {
+        if (user.id === 'user2') {
+          return Promise.resolve(undefined)
+        }
+        return Promise.resolve(user.id as PersonId)
+      })
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual(['user1', 'user3'])
+      expect(mockProvider.getAccount).toHaveBeenCalledTimes(3)
+    })
+
+    it('should handle null latestReviews', async () => {
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: { nodes: [], totalCount: 0 },
+        latestReviews: null as any
+      }
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual([])
+      expect(mockProvider.getAccount).not.toHaveBeenCalled()
+    })
+
+    it('should handle undefined latestReviews', async () => {
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: { nodes: [], totalCount: 0 },
+        latestReviews: undefined as any
+      }
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual([])
+      expect(mockProvider.getAccount).not.toHaveBeenCalled()
+    })
+
+    it('should skip reviews with null author', async () => {
+      const user1: UserInfo = { id: 'user1', login: 'user1' }
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: { nodes: [], totalCount: 0 },
+        latestReviews: {
+          nodes: [
+            { author: null, state: 'APPROVED' } as any,
+            { author: user1, state: 'APPROVED' } as any,
+            { author: null, state: 'CHANGES_REQUESTED' } as any
+          ],
+          totalCount: 3
+        }
+      }
+
+      mockProvider.getAccount.mockImplementation((user: UserInfo) => {
+        return Promise.resolve(user.id as PersonId)
+      })
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual(['user1'])
+      expect(mockProvider.getAccount).toHaveBeenCalledTimes(1)
+    })
+
+    it('should combine reviewRequests and latestReviews', async () => {
+      const user1: UserInfo = { id: 'user1', login: 'user1' }
+      const user2: UserInfo = { id: 'user2', login: 'user2' }
+      const user3: UserInfo = { id: 'user3', login: 'user3' }
+      const user4: UserInfo = { id: 'user4', login: 'user4' }
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: {
+          nodes: [{ requestedReviewer: user1 }, { requestedReviewer: user2 }] as any,
+          totalCount: 2
+        },
+        latestReviews: {
+          nodes: [{ author: user3, state: 'APPROVED' } as any, { author: user4, state: 'CHANGES_REQUESTED' } as any],
+          totalCount: 2
+        }
+      }
+
+      mockProvider.getAccount.mockImplementation((user: UserInfo) => {
+        return Promise.resolve(user.id as PersonId)
+      })
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual(['user1', 'user2', 'user3', 'user4'])
+      expect(mockProvider.getAccount).toHaveBeenCalledTimes(4)
+    })
+
+    it('should handle complex null cases', async () => {
+      const user1: UserInfo = { id: 'user1', login: 'user1' }
+      const user2: UserInfo = { id: 'user2', login: 'user2' }
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: {
+          nodes: [null, { requestedReviewer: null }, { requestedReviewer: user1 }, null] as any,
+          totalCount: 4
+        },
+        latestReviews: {
+          nodes: [null as any, { author: null, state: 'APPROVED' } as any, { author: user2, state: 'APPROVED' } as any],
+          totalCount: 3
+        }
+      }
+
+      mockProvider.getAccount.mockImplementation((user: UserInfo) => {
+        return Promise.resolve(user.id as PersonId)
+      })
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual(['user1', 'user2'])
+      expect(mockProvider.getAccount).toHaveBeenCalledTimes(2)
+    })
+
+    it('should handle empty arrays', async () => {
+      const prData: Partial<PullRequestExternalData> = {
+        reviewRequests: { nodes: [], totalCount: 0 },
+        latestReviews: { nodes: [], totalCount: 0 }
+      }
+
+      const result = await manager.getReviewers(prData as PullRequestExternalData)
+
+      expect(result).toEqual([])
+      expect(mockProvider.getAccount).not.toHaveBeenCalled()
+    })
+  })
+})
diff --git a/services/github/pod-github/src/sync/pullrequests.ts b/services/github/pod-github/src/sync/pullrequests.ts
index e4e22cf05b..11bff84de4 100644
--- a/services/github/pod-github/src/sync/pullrequests.ts
+++ b/services/github/pod-github/src/sync/pullrequests.ts
@@ -317,7 +317,10 @@ export class PullRequestSyncManager extends IssueSyncManagerBase implements DocS
 
   async getReviewers (issue: PullRequestExternalData): Promise<PersonId[]> {
     // Find Assignees and reviewers
-    const ids: UserInfo[] = (issue.reviewRequests.nodes ?? []).map((it: any) => it.requestedReviewer)
+    const ids: UserInfo[] = (issue.reviewRequests?.nodes ?? [])
+      .filter((it: any) => it != null)
+      .map((it: any) => it.requestedReviewer)
+      .filter((id: any) => id != null)
 
     const values: PersonId[] = []
 
@@ -328,7 +331,10 @@ export class PullRequestSyncManager extends IssueSyncManagerBase implements DocS
       }
     }
 
-    for (const n of issue.latestReviews.nodes ?? []) {
+    for (const n of issue.latestReviews?.nodes ?? []) {
+      if (n?.author == null) {
+        continue
+      }
       const acc = await this.provider.getAccount(n.author)
       if (acc !== undefined) {
         values.push(acc)