Hello my mod has stopped firing. Well it fires for around 5 goes then it just stops working for a good 5 minutes. It also turns itself off. And when it's off it takes me a good 2 minutes to turn it back on. I've changed the coils and that is not the problem I've connected the tank upto my old mod and it works perfectly. Does this mean I need to head to the local vape store and buy a new mod ?