Hello and welcome to the Community, Emma83
We'll be happy to help you in updating the bank transactions for your main account in QuickBooks.
First, please try to refresh the account manually by signing into QuickBooks via the web and then select the Settings wheel > Manage account > Click the three lines > Select manage consent > Click reconfirm.
For further troubleshooting, please also try signing into QuickBooks through a different browser or on the app.
Thanks for reaching Intuit QuickBooks support on the Community. We'll be around if you need any further assistance.