PowerApps: Error Updating Rows from Form Input

Hello,

I have created a form for approving discounts that is attached to a PowerBI Report. The form seems to work well other than it not updating existing records that have a matching OrderNumber, but it rather create a new record. I know I could send this approval information to another table and join the two tables later on, but is there a way to just have the input from the edit form update existing records? I have gallery1.selected for the edit form's item property which has worked for me in the past. Any suggestions? Thanks!