My laptop charging stops suddenly.

when I plug in my charger to my laptop it is charging. but at sometime it gets disconnected and it never charge again even when the charger is connected. even when i restart the laptop, it is not charging. I have to remove my battery and put it back then it will charge. it has no pattern. sometimes this happens frequently. but sometimes it doesn't happen. i don't know what is the problem... removing the battery means hard reset right? can anyone help me please... thank you...