Xfinity is Charging me for two Outdated Iphones

I’m not understanding why it’s so hard to understand refunding my my Cc back Xfinity. I made a huge mistake thinking a phone update would go smooth, I returned a IPhone 13 after i unboxed it to , find out it was a smaller device than they rep said was a big sturdy phone it’s smaller than the antiquated device I Paid off!! 2 years ago from Xfinity formerly Comcast. A Rep from overseas stated to give her the Imei # and I would get a $400 discount for this phone , turned off my number that I Ported in !! Gave me a Google Voice # that I already had .Xfinity told me if I returned the device back within 21 days not wet or broken I would be refunded back .I immediately returned it the following day Oct 12 th 2023 I returned it to Fed ex . 2 Days later without any Convo Knowledge Heads up ,they shipped out against my Permission a IPhone 14pro same smaller phone as the iPhone 13 I almost begged them not to they claim it was already in motion this is crazy. I returned this one without even opening the box Oct 22nd 2023.  No refund plus while during the Convo They was slick & billed my card During! The call I was asking about my bread they owe me already they tried to get $141 + $247 now I keep getting emails since 2 wks ago about a 8-10 day refund back nothing but lies & Gaslighting from different ppl with a million versions of not knowing or understanding .I’ve Been a loyal Customer for 14 yrs . now my credit looking crazy they used 2 cards burning  them out. I have 1 phone 1 Line  Why keep charging me for devices but not giving that money back fast like y’all/they took it out  This is Ludicrous unethical & giving Scammy Fraud vibes. Xfinity mobile is charging me for 2(two) Device Payment Plans for 24 months for Devices returned in pristine Condition in Oct, it’s now Dec 6 I need to be be righted its not cool