Starling closing my bank with 90 days notice

I have had my account since 2021, never had any issues. But got a message through the app to say they’re closing my account with 90 days notice and no reason why. I requested my DSAR from them and from Experian, both showing everything normal- nothing unexpected or suspicious. I am now trying to find a new bank account but have been rejected from First Direct, Monzo and Virgin Money.

My credit score isn’t great as I was in a bit of credit card debt which I’ve since paid off, and I have only ever missed 1 payment since opening the credit card in 2019. I am really unsure why I’m being rejected from opening a new account and I’m not sure what to do. I know other people who have worse credit, CCJ’s etc and have been accepted for Monzo. I also read that virgin will offer you a basic bank account if your credit score is that bad however they didn’t offer me one which makes me think there’s another problem. I’m really unsure of what to do next. I haven’t had anything to do with Crypto as I know they don’t like that. I have had one chargeback request for £5 early last year which was legitimate and settled (due to a broadband payment that was taken even though I had cancelled the service). I can’t think of anything else that might have caused me to be debanked