The remote have to work with new batteries. You can check the board where the components are mounted and resoled any that look bad. In your case it could caused by a leaky diodes or a bad solder. All can be replaced at a local electronic or hardware store and they're easy to replace Possible batteries problems: 1 batteries are not making contact properly inside the remote. Test by cleaning connections of the batteries and the remote. 2 battery charger is bad and isn't actually charging the battery. Test by charging on another charger if possible. 3 batteries are bad and are not actually recharging. test by using other batteries if possible. 4 other, unknown, internal remote problem. buy a new one.
Usually answered in minutes!