My landline Pennsylvania Caller ID shows up as coming from Poland, because +1 is missing;

How do I stop my RCN Caller ID from area code 484 stop showing up on my iPhone 12 Mini (OS 16...) as coming from Poland, because of it having country code +48 4......(the rest of my landline's phone number digits)??

It only happens when I call from RCN phone to my T-Mobile iPhone number. Not to my Verizon, Consumer Cellular or other T-Mobile family and friends' who call my cellphone. And they show my correct caller id. Steps taken so far: With T-Mobile tech -- factory reset.