Something's not quite right this transaction has already been accepted

I've got some troubleshooting steps we can perform to get past this error message, brian-krebs713.

What specific transaction are you trying to accept?. There are times when a browser's cache data becomes full of frequently accessed websites or damaged. This causes the error message to appear when accepting transactions. 

To better isolate this one, let's try signing in to your QuickBooks Online (QBO) account using a private or incognito window. This mode doesn't use the existing cache data and helps us confirm browser-related issues. Here's how:

• For Google Chrome browser: Ctrl + Shift + N
• For Mozilla Firefox browser: Ctrl + Shift + P
• For Safari browser: Command + Option + P

If it works, go back to your regular browser and clear the cache to delete those temporarily stored files and browsing history. The overtime collection of data can create corruption, however, removing this should fix the issue. We can also use other supported, up-to-date browsers to roll out the possibility of a browser-related issue.

Feel free to visit our QBO Help Articles page for more insights about running your business in your account. 

I'd like to know how you get on after trying the steps, as I want to ensure this is resolved for you. Feel free to reply to this post and I'll get back to you. You have a good one.