no service at my home

iPhone 7 purchased from xfinity mobile has been an utter nightmare no service at my home once I reach my driveway nothing until I get inside then it’s barely I can hear other but I sound garbled and distorted paid over $500 for a phone that it obvious was a lemon unknowingly my I iphone 4 was working just fine before I got this phone I have had 2 iphone replacements and 4 SIM cards and still the same crazy problem jeopardizing my business interest and personal safety. I have tried everything here but calling Apple which is my next move but if there is an answer out there please share!

Frustrated in Fort Washington MD