Betfair Casino - Account closed but withdraw money declined

Hey i got issue with betfair casino I was deposit £20 and start playing roulette and won £1995 I was contact live chat and give my documents for verification they sed my account is fully verified now I’m able to withdraw my funds I was requested to closed my account permanently as self exclusive and withdraw my money After 2days I check my skrill account I’m not received money yet I was contact live chat my account is closed permanently and I was requested for withdraw remaining funds but it’s been more then 2days still not received my money yet they sed there’s security check on your account we need some documents from you I was sent my documents straight forward after the conversation after one week they replied we need screen shot of your skrill account I was sent it then after few days they emailed again ask holding id photo like selfie I was sent it after few days they again ask new proof of address I was sent it I was contact them via phone ask them what’s going on it’s been two weeks since I’m keep sending my documents you keep asking same documents they sed that’s for verification I sed but my account was already fully verified they sed it’s extra security check I sed I was closed my account here permanently I just need my money that’s it every documents you ask I sent it what you need now they reply wait for the update from our security team finally I get replied my account is closed permanently due to business grounds that’s final decision we refund your initial deposit £20 back in your skrill account I was shocked how that possible I’m not did anything wrong I give my all documents which they ask to me my account was already closed permanently then how they closed twice time same account just for money and give reason business grounds not even tell me what I did wrong why they give my winning I was won with my cash funds I’m not used casino bonus I’m really stress out I was fully cooperate with them they did wrong without any reason given take my all winning I never expect that with them I’m decide take action against them this is really wrong I want my money back £1995