Ok looks like I can’t help that much, sorry.
Mine came direct from Gemtek
Where did you purchase from?
Think as you have established the stumbling block is it’s flashed for mDevices.
If your in EU https://www.comms365.com/ are the importer you might want to try them.
If by chance your going to TTN Conf. Gemtek or Browan as they called now are there.
If you do hit a brick wall I will ask Gemteck directly for you.