This usually happens if you've signed up QuickBooks Online (QBO) separately. One for the trial version and the paid subscription. If you wish to delete the trial subscription, you can cancel it. I'm glad to help you with the detailed process.
First, locate the trial version of QuickBooks, if you have important data from there, you need to export the file for your future needs.
When signing in to your QBO account, the canceled account, will now be listed under the Canceled Companies section on the Please select the company you want to open page and will be deleted on the scheduled time set by QuickBooks.