run the .bat(windows) or .sh(linux) to re-program your SuRG unit's bootloader.

If having trouble runnintg the .bat script on windows, look at updating the JLink.exe file path in Program_Bootloader.bat,as it might be causing the issue.
Or alternatively, just run the .JLink script directly (double clicking)

If you do not have the JLink tools or drivers, you can download them from here: https://www.segger.com/downloads/jlink/