Is recommended that you either turn on flight mode to help speed up charging or turn off your phone. As it can consume just as much power turned on while charging. Making it difficult to charge.
Not sure I agree. I'm definitely seeing a significant drop in charging performance when charging from zero or generally. Switching off the device surely defeats the object... charging should sustain use and also charge the battery. Definitely some code errors that need working out!
This is a real issue following the recent update. My tablet and phone and my wife's tablet all have the same issue. We now use a 45w charger as we get warnings using anything else. Previously no problem using eg usb-c plugged into USB point in wall socket. Samsung need to fix this pronto