Wi-Fi Connectivity

Updated my Samsung Galaxy S5 1 week ago.  Since the update it will not stay connected to wi-fi.  Turns on and off every 30 seconds or so and is draining my battery.  Turned off the smart switch and did not fix.  Had to turn my wi-fi off all together.  Can I go back to factory reset?  Will that clear the update so I can use my wi-fi again?  I have limited data and that doesn't work for me.