What should I do to get help.

3 weeks ago, my cell phone started getting horrible service. I waited a week to see if the issue would go away and nothing. I went into Xfinity store and they could not resolve the issue. They troubleshoot for 2 hours and tried 3 sim cards and then tell me it must be an issue with my phone. They did a backup of my data but I still lost pictures and notes because they were not part of the backup. Phone is kinda new, purchased from Xfinity on a payment plan. They won't help me with the phone, told me to go to Best Buy and work with Geek Squad. Took a week to get with Geek Squad and the diagnostic can back there is no issue with the phone itself. I called Xfinity for a credit and they will not give me one, they actually asked me to do more troubleshooting even though I've already worked with a level 3 tech. I've now purchased another phone plan with a another company. If Xfinity doesn't help me soon, I'll just transfer my service and leave this [Edited: "Language"]. This might be the worst service I've gotten in over 20 years, and phones are not cheap, they tried to get me to Buy a new phone.