diff --git a/src/routes/api/tenants/[id]/agents/[agentId]/absences/[absenceId]/+server.ts b/src/routes/api/tenants/[id]/agents/[agentId]/absences/[absenceId]/+server.ts
index 0b4ec94..9a230a9 100644
--- a/src/routes/api/tenants/[id]/agents/[agentId]/absences/[absenceId]/+server.ts
+++ b/src/routes/api/tenants/[id]/agents/[agentId]/absences/[absenceId]/+server.ts
@@ -340,7 +340,7 @@ export const GET: RequestHandler = async ({ params, locals }) => {
 
     // Check if user is authenticated
     if (!tenantId || !agentId || !absenceId) {
-      return new ValidationError("Missing tenant, agent, or absence ID").toJson();
+      throw new ValidationError("Missing tenant, agent, or absence ID");
     }
 
     checkPermission(locals, tenantId);
diff --git a/src/routes/api/tenants/[id]/appointments/[appointmentId]/cancel/+server.ts b/src/routes/api/tenants/[id]/appointments/[appointmentId]/cancel/+server.ts
index b262e6e..0a00fb0 100644
--- a/src/routes/api/tenants/[id]/appointments/[appointmentId]/cancel/+server.ts
+++ b/src/routes/api/tenants/[id]/appointments/[appointmentId]/cancel/+server.ts
@@ -116,7 +116,7 @@ export const PUT: RequestHandler = async ({ params, locals }) => {
 
     // Check if user is authenticated
     if (!tenantId || !appointmentId) {
-      throw new ValidationError("Tenant ID and appointment ID are required", 400);
+      throw new ValidationError("Tenant ID and appointment ID are required");
     }
 
     checkPermission(locals, tenantId);
diff --git a/src/routes/api/tenants/[id]/channels/+server.ts b/src/routes/api/tenants/[id]/channels/+server.ts
index 7e837cf..af29374 100644
--- a/src/routes/api/tenants/[id]/channels/+server.ts
+++ b/src/routes/api/tenants/[id]/channels/+server.ts
@@ -322,7 +322,7 @@ export const POST: RequestHandler = async ({ params, request, locals }) => {
     const tenantId = params.id;
 
     if (!tenantId) {
-      return json({ error: "No tenant id given" }, { status: 400 });
+      throw new ValidationError(ERRORS.TENANTS.NO_TENANT_ID);
     }
 
     checkPermission(locals, tenantId, true);