Welcome to the Community space, @Amy.
Let me share some insights about why you can't send a payment to a vendor via ach in QuickBooks Online.
I'd like to confirm if there's a specific error message during the payment process. If yes, kindly give us additional information about it. This enables us to investigate it further and provide a solution. In the meantime, to fix this, we can try signing in to your QBO account using a private browser or "incognito" mode. This can help your computer or device run more efficiently by preventing interference from extensions, plugins, or cookies. Here are the shortcut keys for these browsers:
- Google Chrome: press Ctrl + Shift + N
- Mozilla Firefox: press Ctrl + Shift + P
- Microsoft Edge: press Ctrl + Shift + N
- Safari: press Command + Shift + N
Clear your cache and refresh website preferences, which may cause issues with QBO.
I'd also recommend checking out these articles for more details if ever there's an issue getting ACH payments into your bank account, we'll send you an email. The email gives you a specific code, describes the problem, and guides you through what to do: Fix rejected ACH payments or fees in QuickBooks Payments
Feel free to comment below with any questions or concerns about sending payments via ACH in QuickBooks Online. We are here to help. Keep safe!