How do I stop Auto Transaction Matching?

Hello, cadearnel.

The following are the only ones that the system will process automatically when turned on. 

•    Pre-fill forms with previously entered content
•    Automatically apply credits
•    Automatically invoice unbilled activity
•    Automatically apply bill payments

If your transactions are matching automatically, you could have set up a bank rule. To check, go to Banking from the left menu and select Rules. 
If you want to delete it, click on the arrow under ACTIONS and select Delete. 

For additional information about bank rules, please refer to this article: https://quickbooks.intuit.com/community/Banking-and-bank-feeds/How-to-set-and-use-banking-rules-for-downloaded-transactions/m-p/186468

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