diff --git a/apps/api/src/app/app.module.ts b/apps/api/src/app/app.module.ts
index 73f33128a..0aca4e62c 100644
--- a/apps/api/src/app/app.module.ts
+++ b/apps/api/src/app/app.module.ts
@@ -38,7 +38,7 @@ import { GhostfolioModule } from './endpoints/data-providers/ghostfolio/ghostfol
 import { MarketDataModule } from './endpoints/market-data/market-data.module';
 import { PublicModule } from './endpoints/public/public.module';
 import { TagsModule } from './endpoints/tags/tags.module';
-import { WatchlistModule } from './endpoints/watchlists/watchlist.module';
+import { WatchlistModule } from './endpoints/watchlist/watchlist.module';
 import { ExchangeRateModule } from './exchange-rate/exchange-rate.module';
 import { ExportModule } from './export/export.module';
 import { HealthModule } from './health/health.module';
diff --git a/apps/api/src/app/endpoints/watchlists/create-watchlist-item.dto.ts b/apps/api/src/app/endpoints/watchlist/create-watchlist-item.dto.ts
similarity index 83%
rename from apps/api/src/app/endpoints/watchlists/create-watchlist-item.dto.ts
rename to apps/api/src/app/endpoints/watchlist/create-watchlist-item.dto.ts
index 663965ef1..ee2286727 100644
--- a/apps/api/src/app/endpoints/watchlists/create-watchlist-item.dto.ts
+++ b/apps/api/src/app/endpoints/watchlist/create-watchlist-item.dto.ts
@@ -2,7 +2,7 @@ import { DataSource } from '@prisma/client';
 import { IsEnum, IsString } from 'class-validator';
 
 export class CreateWatchlistItemDto {
-  @IsEnum(DataSource)
+  @IsEnum(DataSource, { each: true })
   dataSource: DataSource;
 
   @IsString()
diff --git a/apps/api/src/app/endpoints/watchlists/watchlist.controller.ts b/apps/api/src/app/endpoints/watchlist/watchlist.controller.ts
similarity index 100%
rename from apps/api/src/app/endpoints/watchlists/watchlist.controller.ts
rename to apps/api/src/app/endpoints/watchlist/watchlist.controller.ts
index 0e319d22e..a60a75b9e 100644
--- a/apps/api/src/app/endpoints/watchlists/watchlist.controller.ts
+++ b/apps/api/src/app/endpoints/watchlist/watchlist.controller.ts
@@ -29,13 +29,6 @@ export class WatchlistController {
     private readonly watchlistService: WatchlistService
   ) {}
 
-  @Get()
-  @HasPermission(permissions.readWatchlistItems)
-  @UseGuards(AuthGuard('jwt'), HasPermissionGuard)
-  public async getWatchlistItems(): Promise<AssetProfileIdentifier[]> {
-    return this.watchlistService.getWatchlistItems(this.request.user.id);
-  }
-
   @Post()
   @HasPermission(permissions.createWatchlistItem)
   @UseGuards(AuthGuard('jwt'))
@@ -70,9 +63,16 @@ export class WatchlistController {
     }
 
     return this.watchlistService.deleteWatchlistItem({
-      dataSource: watchlistItem.dataSource,
       symbol,
+      dataSource: watchlistItem.dataSource,
       userId: this.request.user.id
     });
   }
+
+  @Get()
+  @HasPermission(permissions.readWatchlistItems)
+  @UseGuards(AuthGuard('jwt'), HasPermissionGuard)
+  public async getWatchlistItems(): Promise<AssetProfileIdentifier[]> {
+    return this.watchlistService.getWatchlistItems(this.request.user.id);
+  }
 }
diff --git a/apps/api/src/app/endpoints/watchlists/watchlist.module.ts b/apps/api/src/app/endpoints/watchlist/watchlist.module.ts
similarity index 100%
rename from apps/api/src/app/endpoints/watchlists/watchlist.module.ts
rename to apps/api/src/app/endpoints/watchlist/watchlist.module.ts
diff --git a/apps/api/src/app/endpoints/watchlists/watchlist.service.ts b/apps/api/src/app/endpoints/watchlist/watchlist.service.ts
similarity index 69%
rename from apps/api/src/app/endpoints/watchlists/watchlist.service.ts
rename to apps/api/src/app/endpoints/watchlist/watchlist.service.ts
index 408b6fba0..2c7a743cb 100644
--- a/apps/api/src/app/endpoints/watchlists/watchlist.service.ts
+++ b/apps/api/src/app/endpoints/watchlist/watchlist.service.ts
@@ -8,83 +8,72 @@ import { DataSource } from '@prisma/client';
 export class WatchlistService {
   public constructor(private readonly prismaService: PrismaService) {}
 
-  public async getWatchlistItems(
-    userId: string
-  ): Promise<AssetProfileIdentifier[]> {
-    const user = await this.prismaService.user.findUnique({
-      where: {
-        id: userId
-      },
-      select: {
-        watchlist: {
-          select: {
-            dataSource: true,
-            symbol: true
-          }
-        }
-      }
-    });
-
-    if (!user) {
-      throw new NotFoundException(
-        `User watchlist with ID ${userId} not found.`
-      );
-    }
-
-    return user.watchlist ?? [];
-  }
-
   public async createWatchlistItem({
-    userId,
     dataSource,
-    symbol
+    symbol,
+    userId
   }: {
-    userId: string;
     dataSource: DataSource;
     symbol: string;
+    userId: string;
   }): Promise<void> {
     const symbolProfile = await this.prismaService.symbolProfile.findUnique({
-      where: { dataSource_symbol: { dataSource, symbol } }
+      where: {
+        dataSource_symbol: { dataSource, symbol }
+      }
     });
+
     if (!symbolProfile) {
-      throw new NotFoundException(`Symbol ${symbol} not found.`);
+      throw new NotFoundException(
+        `Asset profile not found for ${symbol} (${dataSource}).`
+      );
     }
+
     await this.prismaService.user.update({
-      where: { id: userId },
       data: {
         watchlist: {
           connect: {
-            dataSource_symbol: {
-              dataSource,
-              symbol
-            }
+            dataSource_symbol: { dataSource, symbol }
           }
         }
-      }
+      },
+      where: { id: userId }
     });
   }
 
   public async deleteWatchlistItem({
-    userId,
     dataSource,
-    symbol
+    symbol,
+    userId
   }: {
-    userId: string;
     dataSource: DataSource;
     symbol: string;
+    userId: string;
   }) {
     await this.prismaService.user.update({
-      where: { id: userId },
       data: {
         watchlist: {
           disconnect: {
-            dataSource_symbol: {
-              dataSource,
-              symbol
-            }
+            dataSource_symbol: { dataSource, symbol }
           }
         }
-      }
+      },
+      where: { id: userId }
     });
   }
+
+  public async getWatchlistItems(
+    userId: string
+  ): Promise<AssetProfileIdentifier[]> {
+    const user = await this.prismaService.user.findUnique({
+      select: {
+        watchlist: {
+          select: { dataSource: true, symbol: true }
+        }
+      },
+      where: { id: userId }
+    });
+
+    return user.watchlist ?? [];
+  }
 }