Obtaining a Wise account is 100% free. However, rather than linking your Novo account to Wise, you requested to have your own account credentials with them which is not a requirement to use the integration with Novo.
You would instead, create an account with them, and link your Novo account so that Wise can bill your Novo account. For receiving Wise payments, you'll provide your payer your Novo account information along with any other information that your payer requires.
Novo does not reimburse any fees made from Wise and we suggest reaching out to them if you would like a refund.