I have had this about 2 weeks and have not yet dropped it,yet! I put in my 18650 samsung inr batt and if i turn the battery cap to much it will not turn on. If i back up the cap enough for it to turn on,it wont sit flush/wobbles ,lol. NOW it just suddenly wont be on while im using it and i have to play with the battery cap/door. What in the world? My battery is a flat top and i have tried to look it up,all i see is 18650 but not flat top or button top? Should i be using the button top like AW or flat top like samsung? Also i bought this from fasttech and i have a feeling this will not be an easy return if its messed up. Its is legit Innokin but will they warranty it from fastech if it is broke?