[Resolved]  Samsung India — samsung galaxy j7 max mobile

My mobiles gets switchedoff automatically at my end but when sum1 calls the phone rings at their end but doesnot show any notification to me its in some kind sleep mode and when the battery drains on its own like night or say 7 to 8 hrs and put on charge it starts charging happens once or twice a month but cannot say for sure in feb month it happenened more times what may be the prob is it software issue or any worse