What is the color of the MagSafe plug? Amber or Green. If there is no light then the MagSafe connector is likely dirty or may need replacement [parts|MacBook Pro 13" Retina Display Early 2015|itemtype=magsafe_boards]
If you can install this gem of an App [https://www.coconut-flavour.com/coconutbattery/|CoconutBattery] take a snapshot of the Apps main window and post it here so we can see it.