HTC M8 Won't connect to Sprint Network - ROOTED

[Mick911]

I recently got a used HTC M8 and it's rooted. Recently tried to install it in my Sprint network and it won't factory reset and keeps getting stuck in the TEAMWIN flashing page. I do not know anything about rooting or roms. I just want the phone to connect to my network. While messing with the phone I noticed there is no system update also. I called Sprint and they said I needed to do SYSTEM UPDATE on PRL but the system runs CarbonTEAM and it doesnt show any options. I am a newb on this and need help. I just want to get my phone to connect. THE LTE and 3G would work but cant make phone calls or text.

 

[IAmSixNine]

What model / carrier was it on originally?
If it was a GSM it wont work for Sprint, which is CDMA.