Firebase Cloud Functions with Unity using HTTP-callable function. Help needed.

Hi! I'm trying to send string(name) to Cloud Functions, make Cloud Function do a search in "AllCharacterNames" node by received string(name) from Unity, and then, return found result string back to Unity (even if string null or empty). Problem is - i can't get response back to Unity. I would appreciate if someone help me. Thanks!

My Unity function:

     private void CheckIfNameExists(string name)
             {
                 var function = functions.GetHttpsCallable("checkName");
      
                 function.CallAsync(name).ContinueWithOnMainThread((response) =>
                 {
                     Debug.Log("response = " + response.Result.Data.ToString());
      
                     if (response.IsFaulted || response.IsCanceled)
                     {
                         Firebase.FirebaseException e = response.Exception.Flatten().InnerExceptions[0] as Firebase.FirebaseException;
                         FunctionsErrorCode error = (FunctionsErrorCode)e.ErrorCode;
      
                         Debug.LogError("Fault!");
                         Debug.Log("FunctionsErrorCode! = " + error);
                     }
                     else
                     {
                         string returnedName = response.Result.Data.ToString();
                         if (returnedName == name)
                         {
                             //Name already exists in database
                         }
                         else if (string.IsNullOrEmpty(returnedName))
                         {
                             //Name doesn't exist in database
                         }
                     }
                 });
             }

My Cloud Function:

 const functions = require('firebase-functions');
 const admin = require('firebase-admin');
 admin.initializeApp();
  
 exports.checkName = functions.https.onCall(async (data) => {
  
     const name = data;
     console.log("NAME IS = " + name);
  
     var dbRef = admin.database().ref("AllCharacterNames");
  
     dbRef.orderByValue().equalTo(name).once("value").then((snap) => {
         var exists = (snap.val() !== null);
         if (exists) {
             snap.forEach((childSnapshot) => {
                 var key = childSnapshot.key;
                 var childData = childSnapshot.val();
                 console.log("childData IS = " + childData);
                 return childData;
             })
         }
         return null;
     }).catch(error => {
         console.log(error);
         response.status().send(error);
     });
 });

In Cloud Functions console i can see

console.log("childData IS = " + childData);

result with searched string. Problem is

return childData;

doesn't return that string back to Unity. Am i doing something wrong?