Guys, this problem also on this board:
@baris Thanks for the help. I appreciate it.
@baris Thanks! I got one more question about the composer, but I will post in a different topic.
@Павел-Субач where are they approving user registration? the only place for approval is the ACP.
Double post for solution: Shuffle Signature is the culprit.
many thanks @Julian,
I'll update later today and report back if there's any issues.