TBackendUsers error EMS: Bad request

[Alex_mex 0]

I have an App and backent on RAD Server. To search registered users in my app I'm using the following:

 

BackendUsers1.Users.QueryUserName( UserName, EntityValue, nil);

 

When I was using RAD Studio 11, everything was working just fine, then recently I've moved to RAD Studio 12 and after that my app in widows still working ok, but iOS version gives me an error "EMS: Bad request" exactly on this line of code.

I 've spend a lot of time trying to figure out the problem.

Is there some kind of walkaround, or may be other solution to search users using their names?