diff --git a/server/src/services/asset.service.spec.ts b/server/src/services/asset.service.spec.ts
index 00708c9d1f..322f491695 100755
--- a/server/src/services/asset.service.spec.ts
+++ b/server/src/services/asset.service.spec.ts
@@ -2,7 +2,7 @@ import { BadRequestException } from '@nestjs/common';
 import { DateTime } from 'luxon';
 import { MapAsset } from 'src/dtos/asset-response.dto';
 import { AssetJobName, AssetStatsResponseDto } from 'src/dtos/asset.dto';
-import { AssetStatus, AssetType, AssetVisibility, JobName, JobStatus } from 'src/enum';
+import { AssetMetadataKey, AssetStatus, AssetType, AssetVisibility, JobName, JobStatus } from 'src/enum';
 import { AssetStats } from 'src/repositories/asset.repository';
 import { AssetService } from 'src/services/asset.service';
 import { assetStub } from 'test/fixtures/asset.stub';
@@ -777,4 +777,40 @@ describe(AssetService.name, () => {
       expect(result).toEqual(assets.map((asset) => asset.deviceAssetId));
     });
   });
+
+  describe('upsertMetadata', () => {
+    it('should throw a bad request exception if duplicate keys are sent', async () => {
+      const asset = factory.asset();
+      const items = [
+        { key: AssetMetadataKey.MobileApp, value: { iCloudId: 'id1' } },
+        { key: AssetMetadataKey.MobileApp, value: { iCloudId: 'id1' } },
+      ];
+
+      mocks.access.asset.checkOwnerAccess.mockResolvedValue(new Set([asset.id]));
+
+      await expect(sut.upsertMetadata(authStub.admin, asset.id, { items })).rejects.toThrowError(
+        'Duplicate items are not allowed:',
+      );
+
+      expect(mocks.asset.upsertBulkMetadata).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('upsertBulkMetadata', () => {
+    it('should throw a bad request exception if duplicate keys are sent', async () => {
+      const asset = factory.asset();
+      const items = [
+        { assetId: asset.id, key: AssetMetadataKey.MobileApp, value: { iCloudId: 'id1' } },
+        { assetId: asset.id, key: AssetMetadataKey.MobileApp, value: { iCloudId: 'id1' } },
+      ];
+
+      mocks.access.asset.checkOwnerAccess.mockResolvedValue(new Set([asset.id]));
+
+      await expect(sut.upsertBulkMetadata(authStub.admin, { items })).rejects.toThrowError(
+        'Duplicate items are not allowed:',
+      );
+
+      expect(mocks.asset.upsertBulkMetadata).not.toHaveBeenCalled();
+    });
+  });
 });
diff --git a/server/src/services/asset.service.ts b/server/src/services/asset.service.ts
index 26775a5ce4..b92c339aab 100644
--- a/server/src/services/asset.service.ts
+++ b/server/src/services/asset.service.ts
@@ -414,11 +414,32 @@ export class AssetService extends BaseService {
 
   async upsertBulkMetadata(auth: AuthDto, dto: AssetMetadataBulkUpsertDto): Promise<AssetMetadataBulkResponseDto[]> {
     await this.requireAccess({ auth, permission: Permission.AssetUpdate, ids: dto.items.map((item) => item.assetId) });
+
+    const uniqueKeys = new Set<string>();
+    for (const item of dto.items) {
+      const key = `(${item.assetId}, ${item.key})`;
+      if (uniqueKeys.has(key)) {
+        throw new BadRequestException(`Duplicate items are not allowed: "${key}"`);
+      }
+
+      uniqueKeys.add(key);
+    }
+
     return this.assetRepository.upsertBulkMetadata(dto.items);
   }
 
   async upsertMetadata(auth: AuthDto, id: string, dto: AssetMetadataUpsertDto): Promise<AssetMetadataResponseDto[]> {
     await this.requireAccess({ auth, permission: Permission.AssetUpdate, ids: [id] });
+
+    const uniqueKeys = new Set<string>();
+    for (const { key } of dto.items) {
+      if (uniqueKeys.has(key)) {
+        throw new BadRequestException(`Duplicate items are not allowed: "${key}"`);
+      }
+
+      uniqueKeys.add(key);
+    }
+
     return this.assetRepository.upsertMetadata(id, dto.items);
   }