I need help with my account, I have spent 60 hours talking to people on the phone

Well, I have one. I will keep this short and sweet. I had an iPhone 16 Pro Max, and over the phone, they talked me into trading it in for an iPhone 17 Pro, paid in full over 24 installments. Xfinity messed up the promotion when they keyed in, so I had to call every month to get my credit, which took, on average, 2-3 hours each call. So after the very first call, I asked them to send me my old phone back, and I would send it back to them. I was told that was impossible. That was in November of 2025. I called in at least 20+ times to get my $42 credit. Today I ported my numbers out and told them I would keep their phone if they could not send my old one back. I asked for a ticket or case number; they said they have none. One word of advice: never buy anything from them over the phone; only go into the store. Once you start over the phone, the store really can not help you much. If anyone has a corporate number in the United States, I would greatly appreciate it. For me, it is the principle. They did not provide the service I paid for. I just spent 4 hours on the phone with them today, probably 60-70 hours in total.