SIM error detected heads-up

I have had the same problem, which just recently started. There seems to be a problem the SIM mechanism on the Arcadyan gateway that doesn't positively lock into place with a distinctive click. It's also possible that it was initially clicked into place but worked its way out. At one point it wouldn't eject. To T-Mobile's credit they offered a new gateway, but there's  no guarantee the mechanism on the new one won't be as janky. After working the current SIM card mechanism, it seems to be staying put for now.