QuickBooks Online makes it effortless to manage your recurring transactions. I'd be glad to show you how to delete a recurring transactions.
To do this, follow these steps: Select the Gear icon on the Toolbar > Under Lists, select Recurring Transactions > Click on the drop-down next to Edit > Delete. You should get a confirmation that that particular recurring transaction has been deleted. Try this out and let me know how you make out.
Here are some great resources related to Recurring Transactions. I encourage you to check them out. Feel free to ask questions.