To make matters worse, I tried to charge my customer's card directly from the invoice and now I get the attached message.
When I click on “contact us” it sends me here https://quickbooks.intuit.com/learn-support/en-us
I click again on “contact us” and it redirects me to a page that finally goes to my QB account but I get the message.

“We're sorry, we can't find the page you requested.
You may have incorrectly typed the address (URL) or clicked on an outdated link.”

I tried with 2 different browsers from 2 different computers and I keep getting the same thing.
It is a nightmare.