diff --git a/frontend/src/services/api.ts b/frontend/src/services/api.ts
index e6f0442..8aacbc6 100644
--- a/frontend/src/services/api.ts
+++ b/frontend/src/services/api.ts
@@ -132,11 +132,11 @@ export const toBuyApi = {
 
   },
 
-  addByRecipe: async (recipeId: number, servings: number): Promise<any> => {
+  addByRecipe: async (recipeId: number, servings: number, difference: boolean): Promise<any> => {
     const response = await fetch(`${API_BASE_URL}/api/tobuy/addByRecipe`, {
       method: 'POST',
       headers: getHeaders(),
-      body: JSON.stringify({ recipeId, servings }),
+      body: JSON.stringify({ recipeId, servings, difference }),
     })
     if (!response.ok) {
       throw new Error(TOBUY_ERRORS.CREATE_FAILED);