fix

Author: MisbahAN

api/users/index.ts

@@ -91,7 +91,7 @@ export default async function handler(
       },
     };
 
-    const result = await usersCollection.findOneAndUpdate(
+    const result = await usersCollection.updateOne(
       { firebaseUid },
       {
         $setOnInsert: defaults,
@@ -102,18 +102,19 @@ export default async function handler(
           lastLoginAt: now,
         },
       },
-      { upsert: true, returnDocument: "after" },
+      { upsert: true },
     );
 
-    if (!result.value) {
+    const user = await usersCollection.findOne({ firebaseUid });
+    if (!user) {
       throw new Error("Failed to create or fetch user");
     }
 
-    const wasExisting = Boolean(result.lastErrorObject?.updatedExisting);
+    const wasExisting = result.upsertedCount === 0;
 
     return res.status(wasExisting ? 200 : 201).json({
       success: true,
-      user: result.value,
+      user,
     });
   } catch (error) {
     console.error("Error creating user:", error);