iPhone could not be updated because the firmware file is not compatible

Hello jk10003 and welcome to Apple Support Communities.

I see you're having an issue with an error relating to firmware when trying to update your iPhone to iOS 13.

Take a look at these articles:

If you see an error when you update or restore your iPhone, iPad, or iPod - Apple Support

Get help with iOS update and restore errors - Apple Support

If you try all of the steps listed here and still have this issue, you'll find a link at the very end of the second article that will allow you to contact Apple Support for additional help.

Cheers.

Hi jk10003.

I'm glad to hear you got it resolved!

Cheers.