#proof-of-funds-fee

Is 'Global Fund Recovery' asking for a 'proof of funds' fee just another scam after I lost my crypto?

Okay, so I was stupid enough to fall for a crypto investment scam last year, lost about £8k, my life savings tbh. I reported it to Action Fraud and my bank, but nothing really came of it. Then, out of the blue, I get an email from a company called 'Global Fund Recovery'. They sound really convincing, sent me some documents, even had a 'case number'. They claim they've traced my funds to a specific wallet and can get them back, but they need a 'proof of funds' fee, about £700, to 'unlock' the assets. They said it's a standard banking procedure for international transfers. My gut is screaming scam again, but a small part of me is desperate. Has anyone dealt with these guys or heard of this fee before? I really can't afford to lose any more money.