I have connected my bank account to my account but nothing come up and keeps saying I need to reconnect the bank account.

Hello there, @prcgardens.

 For me to verify and check for any open investigation, may ask the name of your bank any details will be much appreciated.

In the meantime, let's manually upload your bank transactions in QuickBooks, here's how:

1. Click the Banking menu, then Banking. 
2. Select the account you want to update, then click Update. 
3. For security reason some bank requires authentication, then enter your Multi-Factor Authentication (MFA) credentials. Then tap Continue update. 

You'll get notification once update is successfully finished. Check your bank feed again for the missing transaction and categorise it into the correct account.

For additional information on this, I recommend the following article: What to do if you can’t find downloaded bank transactions. It also includes troubleshooting steps to fix specific download errors in case you encounter any during manual update. 

You may also read these articles to learn more about online banking:

• How to use Online Banking, Connect Bank Accounts, and Review your Bank Feed in QuickBooks Online
• Learn the reconcile workflow in QuickBooks

Keep me posted if you have any other questions about banking. I'll be glad to lend a hand. Take care.