Don't get mobile lines through Xfinity - charged for a year for a line for a phone that was sent to Xfinity

Do not utilize mobile services. I have been a loyal customer since I bought my house 09/2021 and have used their phone services since 2023. I spoke with a rep and ordered the iPhone 15 Max Pro with them at the time. I sent them my iPhone 14 Plus Starlight for a credit and the line was never shut down. They have been charging me for the line though it was never activated. I caught it, though I trusted my autopay, because I thought my phone should be paid off due to the expense of the monthly bill- I had been being billed for a second line this entire time. Xfinity will not make it right even though services were not rendered and they device is in their possession and are only willing to refund two of the 18 months. Meanwhile, I have had service interruptions and issues with my internet and have offered patience and loyalty. You would think that no services being rendered, being able to profit on my device and continued use of their services would have had this process look differently for me. Additionally, I have neurodivergent disabilities - please check on your loved one to ensure they aren't being taken advantage of.