South s6 radio

Hi guys,
My external radios (South S6), two of them, just stopped working at the same time. I have tried changing channels and protocols but they won’t transmit any corrections, perhaps they need firmware update or something.
Please assist.
Thank you
Mike

Hi Mike,
Please feedback the SN of this two S6 radio, and from which seller you bought them? we will inform him to follow your support directly.