Netgear Nighthawk M1 Charging Issues

Hello, so I’ve been using the NETGEAR Nighthawk M1 MR1100 Mobile Router for a while now. And I noticed a little issue with the charging, whenever I leave it charging overnight (while it’s at 13% of charge) and check back in the morning, it doesn’t charge as fast meaning it will be at about 24% after a day of charging. And this really annoys me because I always take my Mobile Router with me whenever I go outside, and it always runs out of battery because of this issue.

Before you ask me these:

1- I cleaned the Gold contacts both on the battery and the device.
2- I soft restarted the device.
3- I took out the battery out of the device and waited for over 30 seconds.
4- The cable is not damaged nor the battery or the device it self. (I doubled checked).