Sending good vibes to you, pwoodward.
Let me help and get you pointed in the direction so you can notify your provider about credit card convenience fee.
In order to notify your provider about the credit card fee, I recommend reaching out directly to our QuickBooks Payments Support. You would have to call since credit card information is confidential, and we value your privacy.
You can get our most-up-to-date contact number here: https://community.intuit.com/browse/payments-contact-us.
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Keep me posted if you still need help about credit card fees in QuickBooks Online.