Hi @nishantc
Try replacing the battery pack (or the batteries) and check if that resolves the problem. Even rechargeable batteries have a lifespan.
Here's a [https://www.youtube.com/watch?v=_UDhxITTASs|video] that may help. Go to 3:09 minutes to view the battery pack location.
There is a complete battery pack available, search online for ''SUN-INTE-125,'' to find suppliers or you can replace the individual battery cells, search online for ''18650 2600mAH Li-On battery with solder tabs.'' You will need 8 of the individual battery cells
***Note:*** Having the "solder tabs" already on the battery means that less heat is required when you go to solder them to the battery management board as opposed to batteries that don't have them and you need to solder them in. Applying too much heat to these batteries is not a good idea. Also remember to dispose of the old batteries [https://www.ifixit.com/News/34034/lithium-ion-batteries-are-a-literal-trash-fire-and-getting-worse|responsibly]