I just bought it a week ago. it was working just fine last night. The battery is fully charged. I have two clearomizers and two mods. I have the Aspire Atlantis and Kangertech Clearomizer and the Variant box mod and the Itaste VTR. When I screwed in the Kangertech into my Itaste VTR I was working just fine so the coil isnt dead. The coil is brand new for both of them. When I screwed in the Kangertech to the Variant, it says "check atty" on the screen and wont vape. It does the same thing with any other atomizer. It was working just fine yesterday. What could I do about this? Is it defective?