diff --git a/CHANGELOG.md b/CHANGELOG.md
index ac62bb06c..ffa35cf41 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- Simplified the data source check in the DTO of the activity creation
+- Simplified the data source check in the DTO of the asset profile update
 - Renamed `User` to `user` in the `Subscription` database schema
 - Migrated the `@ghostfolio/ui/assistant` component to control flow
 - Migrated the `@ghostfolio/ui/value` component to control flow
diff --git a/apps/api/src/app/admin/update-asset-profile.dto.ts b/apps/api/src/app/admin/update-asset-profile.dto.ts
index 45923410a..5056dccdb 100644
--- a/apps/api/src/app/admin/update-asset-profile.dto.ts
+++ b/apps/api/src/app/admin/update-asset-profile.dto.ts
@@ -32,7 +32,7 @@ export class UpdateAssetProfileDto {
   @IsOptional()
   currency?: string;
 
-  @IsEnum(DataSource, { each: true })
+  @IsEnum(DataSource)
   @IsOptional()
   dataSource?: DataSource;
 
diff --git a/apps/api/src/app/order/create-order.dto.ts b/apps/api/src/app/order/create-order.dto.ts
index f40e65ba1..c2b10fd81 100644
--- a/apps/api/src/app/order/create-order.dto.ts
+++ b/apps/api/src/app/order/create-order.dto.ts
@@ -49,7 +49,7 @@ export class CreateOrderDto {
   @IsOptional()
   customCurrency?: string;
 
-  @IsEnum(DataSource, { each: true })
+  @IsEnum(DataSource)
   @IsOptional()
   dataSource?: DataSource;
 
diff --git a/test/import/invalid-data-source.json b/test/import/invalid-data-source.json
new file mode 100644
index 000000000..472e295ee
--- /dev/null
+++ b/test/import/invalid-data-source.json
@@ -0,0 +1,18 @@
+{
+  "meta": {
+    "date": "2021-01-01T00:00:00.000Z",
+    "version": "dev"
+  },
+  "activities": [
+    {
+      "currency": "USD",
+      "dataSource": "<invalid>",
+      "date": "2021-01-01T00:00:00.000Z",
+      "fee": 0,
+      "quantity": 20,
+      "symbol": "AAPL",
+      "type": "BUY",
+      "unitPrice": 100.0
+    }
+  ]
+}