Don't recommend Melio is a childs pay Co, they are unprofessional & have to many issues. QBO should have never allow this Co. to work wQBO, they waste bus owners time.

Any specific issue? Is it related to Bill Payment feature powered by them or getting the payment with them?

https://melio.grsm.io/quickbooks

Utilize another app to pay bills if required.

https://veem.grsm.io/veems

Had high hopes for Quickbooks payments and have a tone of difficulty making it work with Melio.  Seems very buggy and response and follow up to questions I have is way too slow and hasn't resolved the issues.

@Robert_Benjamin 

Explore a paid app as another option.

https://billcom.grsm.io/quickbooks

Yeah I am familiar with Bill.com but another paid third party app is a poor solution as Melio is included integrated payment App for Quickbooks online paid subscription and if it isn't working properly Intuit should drop them for someone better or develop their own payment processing system.