When I put my charger in my iPhone XR it just stop working after a good week, even brand new chargers. Is it my phone?

Check the Battery Health on the iPhone as follows:

Home Screen > Settings > Battery > Battery Health

If the Battery Health is less than around 80%, you need to replace the battery.

iPhone Battery & Power Repair - Apple SupportOfficial Apple Support › iphone › repair › service

If the Battery Health checks out OK, best to take the iPhone and charger in to an Apple Store or Apple Servicer to let them take a look.

Perhaps it is the phone. It would be a good idea to make an appointment at the nearest Apple Store for an evaluation and explanation of your options.

Apple Store - Find a Store - Apple