I feel they are asking for a US bank account not a UK bank account otherwise they’d possibly be asking for a IBAN. You need a US bank account or use Transferwise borderless account as suggested which includes the US bank details such as:
Wire transfer number.
Routing number.
Account number.
I would clarify this with the company paying you.
Monzo also doesn’t reliably receive international transfers right now. They are working on it.