Flamed out

My first 18650, a Trustfire flame, has died. The other from the pack is still going strong. This one reads 0. If I put it on the TR-001 it starts up again. I charged it some on my Xtar charger and it went from about 3.1 to 3.7 volts. I went back to it later and it wouldn’t charge. 0 volts again. Maybe the PCB just went bad, but I won’t use or charge it like this.

Pcb may be disconnected. There should be some voltage left in it.

Remove the protection board and check it

Sounds like the PCB isn't making connection. If you press it down with your DMM will it show a voltage?