[Q] Problem with flashing Android 5.0 to Pageplus topic

Hello, XDA members! I am in dire need of help. I recently factory reset my Samsung Galaxy Note 3 (US Cellular, had Android 5.0). Because my phone was flashed to Pageplus and I reset it, I am not able to make any sort of calls. Now here's the problem: When I went to Pageplus to flash my phone, they said they are not able to "speak" to the phone because of there not being a way to flash Android 5.0 phones (That surprised me). I'm just an ordinary consumer, so I do not have a lot of knowledge about tech. I was hoping you guys could help me. Thanks.

P.S. I hope this is the correct place to post this in the forums.