sd card

Hi, I have recently received a free Solo from a friend and it was working :) But... I stupidly got faster in doing than thinking and reading and factrory reseted the controler. Since the Solo was not in use from 2016 I got PreFlight update thing. So then I started to read. Now I have Solex on...

My controller will no longer connect to solo. yes i have done the sd card thing where you take it out and put it back in, and i have also factory reset both controller and drone. yet the drone and controller proceed to have the problem happen time and time again. im wondering if anyone knows of...