iPhone charging only when powered ON.

Hi! I got an iphone 6s that is NOT water damaged and it is charging only when it is powered ON. If the phone is switched OFF( turned OFF completely ) it wont charge and it wont boot up when i plug the charger like it should do. I also saw that it has a normal and fast boot, and when it is powered ON with screen OFF it is taking(measured on battery slot) 0.11A then jumps to 0.15A then goes back to 0.11A all over the time!

I measured that on an OK iphone 6 and when powered ON with screen turned OFF, it takes absolutely 0.00A, so that must happen on my iphone 6s too, but i dont know why it dont.

Becasue of that, of course the battery drains faster ( about 5-6% per hour) doint nothing on my phone, and it is charging a little harder than it should.

I also realized that my phone says that my screen was turned off only 19 minutes, even if i didnt touched the phone for a day.

After doing some research i think it might be TRISTAR IC, but i want to know your opinions!

Thank you!