You are receiving the below error message when attempting to create a contact on an invoice.
ErrorCode:2220, Message:Invalid Currency type, Element:Currency, Detail:Invalid or Unsupported currency type supplied. Supplied value:None
QuickBooks Online integrated companies.
Add Contact function on invoices.
This error means that multicurrency is not enabled for the company on your QuickBooks Online account.
To clear this error, please do the following: