Overheating devoce

My fiance and I purchased 2 Sony Xperia L1 these 2 devices are less than 3 months these devices heat up while charging or even from minimal usage the battery doesn't last as advertised everything is going wrong with these devices, contacted Sony through emails they suggesting an option we tried and still doing the same called Sony nobody answers in English spent R150 o. Airtime with no success.

Please resolve this