Seller payment Details Invalid as seller account has been suddenly closed

I’m buying some bitcoin from a seller.
Once the trade started, I tried to pay and the seller but the payment details were invalid (N26 MoneyBeam).
Chatted with seller and he said the N26 bank cancelled his account.
He suggested to switch to SEPA or cancel.
If we do SEPA, the details in the Signed contract are different, and I wouldn’t have a way to protect myself.
What would you suggest to do next ?
How can we switch to SEPA updating the contract ?

Let the mediator handle this, you can open mediation before the trade period ends with ctrl+O. You don’t have to send send funds to a different account if you don’t want to, but at least I would require that the seller account has the same name.