I've tried deleting a duplicated invoice and payment record to a customer account several times but the page just spins and doesn't complete the deletion.

Let's work together and get this sorted out, @thecotswoldsprop. 

We can perform some troubleshooting steps to rule out any browser-related issues.

Let's start with opening your QuickBooks Online account in an incognito or private browser. This mode will not save your browsing history and will also help isolate any web issues. 

Here are the keyboard shortcuts:

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

Next, sign in to your QuickBooks Online account and confirm. If the page can load the information with no problems, go back to your regular browser and clear its cache. Clearing the cache fixes certain problems, like loading or formatting issues on sites. It also helps pages to load faster.

Lastly, restart your browser to update the settings. In addition, you can use a different supported browser.

Additionally, I'll be sharing these relevant articles to help manage your bank transactions in QuickBooks:

• Match and categorise
• Reconcile bank accounts

Feel free to get back in here if you have further concerns with your bank transactions in QuickBooks. I'm always around to help. Keep safe!