You're referring to deleting a recurring transaction/template for invoices in QuickBooks Online (QBO), correct? If so, this can be done in three easy steps. Here's how:
In QBO, go to the Gear icon at the top right to get to the Recurring Transactions.
Click the Edit drop-down under the Action column, then choose Delete.
Hit Yes to confirm.
To learn more about managing recurring transactions or templates, consider checking out these articles: