Let's try add an additional number so that the unit has some information to download.
We start by dialling *#0007, *#0004 from the cellphone number of the intercom.
Wait 5 minutes and then test again by dialling *#0003
Send an SMS with the word “Reboot” to the cellphone number of the intercom.
Wait 5 minutes and then send an SMS with the word “Update” to the cellphone number of the intercom.
Wait 10 minutes and then dial *#0003 to test again.