I had my Orange phone number ported to a Vodafone pay as you go SIM.

Today I switched the phone on and it said "SIM Card registration
failed". I hadn't used the phone in some time so I assumed they had
disconnected it again. I phoned up Vodafone to try and get it
reconnected and they just said it couldn't be done. I should have made
a call at least every 90 days to keep it connected.

I'm slightly annoyed at this. I've lost the phone number that I've had
for 10 years and all the credit that was on the phone.

Is there a PAYG tariff available that will allow me to keep a number
without using the phone very much?