Yesterday my Pay As You Go credit suddenly dropped from £5-6 to 0.00. I couldn’t figure out the reason for that until I found out that it was exactly a year (365 days) after my last top-up. That said, I was regularly making chargeable calls, texts and using my data throughout that period. So, what happened is inconsistent with what iD Mobile says…
https://community.idmobile.co.uk/pay-as-you-go-106/how-long-does-a-top-up-last-33939#comments
Topic: "How long does a Top-up last?"
Answer: "Your Top-up will expire if you don't use your phone for 365 days."
https://community.idmobile.co.uk/top-ups-175/pay-as-you-go-top-ups-44961
F.A.Q. Topic: "Pay as you go top-ups"
Question: "How long does a top-up last?"
Answer: "Your top-up will expire if you don’t use your phone for 365 days. To prevent this from happening, you must make one chargeable call, text or use some of your mobile data sometime within those 365 days."
I sent a PM to the iD Mobile account here but they probably do not monitor it. Once I top up my phone, so that I can make calls again, I may call iD support about this matter, however, I don’t think that it'll make any sense because, if I remember well, their people speaking on the phone are ill-informed and unaware of their actual terms/conditions stated on the community website.
I wish iD Mobile employees will take a look at this thread.