Thank you for following up with us, @doctorfizzix. Let me provide additional insights about your experience with ACH payments.

First, you can see the applicable R code on the email message sent from Intuit. From that email, we also provide you a link to where you can upload the completed bank letter from your bank to resolve the issue. The bank letter is necessary for legal purposes. It's a confirmation from your bank that clear any possible issues that affect the declined transaction.

Since you or your vendor doesn't receive any email messages from us, review your spam messages to narrow down the result. Also, please ensure that the email information is valid and correct under the Company Settings window. Your vendor can follow these steps:

1. Open QuickBooks.
2. Go to the Gear icon, then click on Account and Settings.
3. Click on the Company section, and review the details under Contact info. Modify if needed.
4. Hit Done, then Save.

Alternatively, you may reach out to our Merchant Team for more details about the problem. From there, they can guide you on the possible solutions to isolate the issue as quickly as possible. Check out this link for the contact details: Contact Payments or Point of Sale Support.

Once done, see the resources from these links as your tips while handling declined or rejected payments:

• Handle a rejected or failed bank transfer payment
• Fix rejected ACH payments or fees in QuickBooks Payments

If you have follow-up questions in mind, please let me know by leaving a comment below. I'm more than happy to help you again. Have a good one!