So this might need to go under battaries but not sure exactly what the issue is here. I bought my gf a mini about 4 months ago. She really loves it and i got it because i used to have one and know they're bullet proof. So we got her 3 IMR 18350s and lately it seems she will have a fully charged battery use it for maybe 15 puffs at 3.4 volts and the ecig will blink as if the battery is done. So were trying to figure out whats going on here. The atty is a aspire naut at 1.6 ohms. The batterys use to last all day and she usually vapes them until she no longer can. So we wanna find out whats wrong on that front. She wants two new batts for xmas hoping that will help. I need a good 18350 flat top thats not an efest. Idk if thats realistic though because idk if the mod is jacked or the batts. Any help would be very appreciated!! Sorry this post is so long. Any more info needed to evaluate the situation let me know. Ive sub ohmed for a year now and am not good with this stuff. Thanks!!