This is not a scam, it is called a freeze of funds and is done by all payment processors, banks and financial institutions if necessary
You must answer the questions, send the documents and solve all the pending issues in the coming weeks and you will get your money back... if this is not a problem for you, then there is no reason to worry.
I had money locked for 16 months in Ecopayz and after that they returned the money, there are complicated institutions to deal with, but that doesn't mean they are scammers.