Cannot boot phone cannot enter recovery cannot flash via odin Sprint S6

[Android Central Question]

I have a Galaxy S6 SM-G920p. My phone started locking up and rebooting randomly and eventually would not boot. I booted to recovery and did a factory reset hoping to fix the problem but it continued and now it will not even boot to recovery. The only mode i can access is download/odin mode. I tried to flash the rom using odin 3.12.3. It fails every time. So I tried to flash twrp so but the phone always says custom binary recovery blocked by frp lock. All the solutions I have seen for that problem involve changing settings in the phone once it is booted up, something I cannot do. Any ideas?