Your iPad might not charge from a computer if the USB port doesn’t provide enough power. Try using the original wall charger or a different USB port. Also, check the cable for damage and make sure the port on your iPad is clean.
It might be because some computer USB ports don’t provide enough power to charge an iPad properly. Try using the original iPad charger with a wall outlet, or check if the USB port supports charging. Also, make sure your cable is not damaged.