Slow charging, random wake-up and dead USB connections

My phone, Asus Zenfone 5 (A501CG), takes too much of time to charge (6-7 hours). Also, the screen wakes up randomly every 5 seconds (approx.). The phone doesn't connect to a PC (it's not recognized) and OTG doesn't work either. In Settings, it shows that the phone is charging on USB even when it's charging on AC. It happens in safe mode too. What can be the issue? Can a faulty micro-USB port cause this?