diff --git a/src/lib/services/feature-toggle-service.ts b/src/lib/services/feature-toggle-service.ts
index 65ec3fde46..d359764e60 100644
--- a/src/lib/services/feature-toggle-service.ts
+++ b/src/lib/services/feature-toggle-service.ts
@@ -1837,17 +1837,14 @@ class FeatureToggleService {
     ): Promise<IVariant[]> {
         await variantsArraySchema.validateAsync(newVariants);
         const fixedVariants = this.fixVariantWeights(newVariants);
-        const oldVariants: { [env: string]: IVariant[] } = environments.reduce(
-            async (result, environment) => {
-                result[environment] = await this.featureEnvironmentStore.get({
-                    featureName,
-                    environment,
-                });
-                return result;
-            },
-            {},
-        );
-
+        const oldVariants: { [env: string]: IVariant[] } = {};
+        for (const env of environments) {
+            const featureEnv = await this.featureEnvironmentStore.get({
+                featureName,
+                environment: env,
+            });
+            oldVariants[env] = featureEnv.variants || [];
+        }
         await this.eventStore.batchStore(
             environments.map(
                 (environment) =>
diff --git a/src/test/e2e/api/admin/project/variants.e2e.test.ts b/src/test/e2e/api/admin/project/variants.e2e.test.ts
index 4327135ee5..6f7762d08e 100644
--- a/src/test/e2e/api/admin/project/variants.e2e.test.ts
+++ b/src/test/e2e/api/admin/project/variants.e2e.test.ts
@@ -305,6 +305,25 @@ test('Can push variants to multiple environments', async () => {
         });
 });
 
+test("Returns proper error if project and/or feature toggle doesn't exist", async () => {
+    await app.request
+        .put(
+            `/api/admin/projects/nonexistent/features/undefined/variants-batch`,
+        )
+        .send({
+            variants: [
+                {
+                    name: 'new-variant-1',
+                    stickiness: 'default',
+                    weight: 500,
+                    weightType: WeightType.VARIABLE,
+                },
+            ],
+            environments: ['development', 'production'],
+        })
+        .expect(404);
+});
+
 test('Can add variant for a feature', async () => {
     const featureName = 'feature-variants-patch-add';
     const variantName = 'fancy-variant-patch';