O2

I have a PAYG phone that is used sporadically.The credit keeps disappearing - presumably due to lack of use. Are there any accounts where this doesn't happen.The account doesn't need data....or even really unlimited texts or calls

This is a variation on a theme I guess for everyone.In an ongoing role reversal my son has given me his old phone which appears to be sim locked to o2 - he has now gone abroad for 10 days so whilst contactable it’s taking a little time to correspond ...