returns

I am trying to return 2 devices (modem, Flex TV) but have been trying for quite a while to get a return shipping label for both devices with no success.  I have tried Xfinity Assistant, Live Chat, talked to a representative on the phone (who put me on hold for a while, then came back and told me both her and her supervisor were trying to resolve the issue and she would email me with an answer, but since then I have not had anyone get back to me).  Now I continue to get auto calls and text messages reminding me that I need to return my equipment before I start getting charged for it.  I don't know where else to turn, and I am tired of spending so much time on this - it should not be this difficult.  I no longer live in an area that Xfinity services, so there are no stores near me where I can try to return the devices.  I took them to the UPS store but they wouldn't take them without a shipping label.  Any advice on where I can turn?  I definitely don't want to start getting charged, especially when I am spending so much time trying to get someone to help me.  I would appreciate any help I can get!