Hello there, Peter. Deleting a bank account is unavailable. However, you can disconnect it from the Bank transaction page. I'm here to guide you through the steps.
Here's how:
- Go to Transactions and select Bank transactions.
- Click on the Pencil icon on your bank's tile.
- Choose Edit account info and tick the Disconnect this account on save box.
- Click Save to finalize the disconnection.

For more detailed information, please refer to this article: Disconnect accounts connected to online banking in QuickBooks Online.
On the other hand, if the account isn't connected to a bank or credit card, you can inactivate it. Please refer to this article for guidance: Make an account inactive on your chart of accounts in QuickBooks Online.
You can then reconnect the bank account to start fresh.
Regarding the issues with bank transactions not showing up in QuickBooks Online, it might be due to the transactions not being cleared by the bank yet. If you could provide more details about this specific issue, it would help us to provide a more tailored response.
Moreover, to enhance your QuickBooks experience, consider collaborating with our QuickBooks Live Expert Assisted team. These financial professionals specialize in streamlining processes and providing tailored advice to meet your business's unique needs.
Additionally, ensure to reconcile your accounts to keep them accurate and up-to-date.
Please return to this thread if you need further assistance with the process, Peter. We're here to help you in any way we can.