I received a message that says “A Network Error Has Occurred”

The mobile network has rejected a message being sent by the device. This is primarily due to an incorrect phone number programmed into the Phone List. The Message will only ever be sent to Ph1 (the Master Phone). Use the phones command to list the phones. Try changing numbers to international format (+<Country Code, e.g. +61 for Australia)Look for numbers that are too long or short (no more than 13 digits including the country code prefix)Verify the phone numbers by sending them an SMS message from your phone in case the number is disconnected or not recognised.