Why Fast Charger Is Not Charging Fast. Check for Loose Connections and Damages. As most devices now are fast compatible I expect to slowly see.

It allows them to recharge faster over USB connections than they normally would. When I try to enable the super fast charging on my s20 ultra the toggles for both the fast charging and super fast charging are grayed out and will not let me change them. Turn off your phone plug in the charger and check if fast charging is working properly.
This effect is even worse if you buy really long USB charger cables you get a longer cable at the price of charging speed.
Fast charging may not be available with third-party chargers and cables. After this plug in the phone with the original charger and see if fast charging is working properly now. Your device might not support fast charging. Turn off your phone plug in the charger and check if fast charging is working properly.

