Yes I had many problems with other casinos here before, turns out most of them were scammers and got red flag afterwards (ex: coinplay, ole777, 1xbit).
As of Betby (the provider) flagging me, I find quite hard since I still have active accounts on other sites, but I don't doubt it tbh.
I appreciate your help
Have you been able to make withdrawals from those other active accounts as well? The only way of finding out if the provider flagged you if you win and attempt to withdraw.
But you deserve an explanation from them on which terms of services exactly you breached. Insist on them telling whether it was something to do with multi accounting, betting patterns, VPN usage etc.