there is a very real chance you are under investigation by SOCA and the banks wont tell you shit because they can go to jail for tipping off. if they where closing the account because you where using it as a business or whatnot they would tell you, them not saying anything makes me think its something very serious and going on at them about it won't make them tell you, the fact they are hanging up on you makes me think there is a note on your account saying your a suspect in a fraud investigation or something and nobody wants to get fired/ arresed for letting something slip they shouldn't.
Exactly, them not giving you any explanation whatsoever, is most likely because they're not allowed to tell.
It's like calling the phone company and asking about a strange sound that you hear when making calls or picking up your phone => phone t.
"well sir, I'm sorry to inform you, but there's a tap on your phone"
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