Hello @laura48,
At this time, you're unable to update your bank transaction from debit to post it as a credit into your bank account. Because all data of your online transactions downloaded into your account depends on what information has been shared by your bank.
That being said, I'd recommend contacting the Technical Support of your bank so you set up and manually update the posting account of your online transactions. This way, they'll be posted as a debit or credit once you've chosen the correct affected accounts.
I've got your this article for more insights about your online transactions: Create rules to speed up reviews in QuickBooks Self-Employed.
You may also find this article helpful in categorizing your online transactions: Exclude or delete transactions.
Let me know in the comment section down below if you have any other questions. I'm always around happy to help.
