It's quite strange if you don't get any reason with this lock. This is actually exactly what happened last 2020 for maintenance reasons. But more than that, this service several times applies new rules that were not previously written on their ToS page so that users are not aware of it.
My account got locked after that time. I bet they did this large scale scam two more then two times already.
I wonder if its possible to get a proof of balance. I am afraid they just delete my account and I dont have any proof and nobody beleave me.