I’ve heard of the three blinks happening at 3.7v. It should blink for a while and then step down, but not turn off. It sounds like yours is very timid. Thinking about it now, its almost as if Acebeam thought the turbo was a secondary feature and not important for many people. Whatever it is, its incredibly stupid. For me its, worse with the smaller batteries, 21700>14500>16340.