Refund issues

Ive been waiting for a refund due to me from when I had to cancel home security services because I moved from Xfinity since July 2020. I’ve called more than 10 times since then to see why I haven’t received the refund check. I always speak to someone overseas and each person I speak to always guarantee to me that a check will be going out in the mail. They’ve “attempted” to send me my refund check over 4 times, verified my address all those times, and till this day I have not received my refund check almost a year later. I spoke to a supervisor Jason who asked me for card info so they can issue a credit to my card but never seen a credit back to my account. I’ve spoke to another supervisor who said refunds can only be issued by check..... at this point I feel like I’m being lied to. If I am receiving my bills in the mail why have I not received my refund check that I’ve been waiting for almost a year now? You can’t keep blaming covid and mail being slow because I am getting these bills but NOT my refund check. This is terrible customer service. I need someone to help me clarify what the issue is.