Thanks for bringing this into our attention, @andrew-L.
There are times that too much cache files stored in the browser can cause unexpected behavior with the product. It would be best to perform some basic troubleshooting steps to fix this.
To start, let's logging in to your QuickBooks Online (QBO) account via a private browser. It's also a great way to isolate the issue since it doesn't store data in the cache.
Please use these shortcut keys to access a private browser:
- Google Chrome: Ctrl + Shift + N
- Mozilla Firefox: Ctrl + Shift + N
- Safari: Command + Option + N
Then, let's go back to the Split transaction page and enter the transactions then click the Tab to go to the next box. If it works, then you need to clear your browser's cache so the system can start fresh. This way, the stored cache will be deleted on the browser so it'll function efficiently.
You can also use another supported browser as an alternative if you still experiencing this unexpected behavior.
You can get more details about the matching process as well as categorizing your transactions in these articles:
- Match and categorize bank transactions in QuickBooks Online
- Assign, categorize, edit, and add your downloaded banking transactions
Once done, you can start reconciling your bank account. You can follow the steps in this article: Reconcile an account in QuickBooks Online.
Please let me know if you need further assistance, or if there's anything else I can do for you. I'll be happy to help you some more.