Over time, software can become cluttered. A fresh install of the stock firmware restores that "out-of-the-box" speed.
Ensure you are using the original USB cable and that you are in Download Mode. official samsung galaxy a20 sma205f ds stock rom
(Use this instead of CSC if you want to keep data, though a clean flash with CSC is recommended). Step 2: Put Your Galaxy A20 into Download Mode Power off your phone completely. Over time, software can become cluttered