At times my phone won't charge, it will remain at same percentage of charging level. and it shows expected charge time 5 hrs 45 min etc..but this won't happens regularly, monthly once or twice it happens.Any issue in hardware ?

Since yesterday, most of the contact either renamed or numbers merged with other name. for E.g..1. ph no. 98..001 was Mr. A now it has become Mr z.2. ph no. 98..002 earlier stored as Mr B , now merged into Mr C along with Mr. c's original number.I u...