Hi there, farahhussain21.
We hate to see you go. However, we respect your decision to cancel your account.
I think this the article you followed: Cancel your QuickBooks Online subscription or trial. Let's do some browser troubleshooting steps, then you can try canceling your account.
To start, you can log in to QuickBooks in a private browser and try to cancel QuickBooks. This blocks the cache from saving new data which could have caused the blank-page behavior. If the same thing happens, please clear the cache in your browser and add intuit to the trusted site, or try other browsers.
If you're still stuck, please contact the number in the article.
We're just around if you need more help.