If you're sure that nothing (cover or screen protector) obstructs or interferes with your touch screen (should be this case, try to remove it/them), perform a "forced" restart of your 13, using these instructions:--> Force restart iPhone – Apple Support.
If the issue persists, for your peace of mind, make an appointment (*) and have your device inspected at an Apple Store or AASP (Apple Authorized Service Provider) among this list:--> Apple – Location Selector. After checking it out, they'll give you all the available options.
Regards
Giulio
(*) You can do it: