Fuddy Duddy GrandMa Phone

If you haven't used your phone for a while, there is a chance that it will be disconnected by virgin. If you telephone customer services from another phone they will get you going again. I have a spare old Vodafone with a very long battery life, for emergencies, in my bag packed in case I get rushed to hospital (I am fit and healthy!) On the first of each month I send one text from it to keep it live.
I hope you manage to sort this out.

I know it's a bit of an obvious question but, you have got plenty of credit left on your phone haven't you? If you have and you still aren't able to make calls or send text messages, you'll have to call Virgin Media on 150 and ask them what's going on. But they do have a clause in their PayAsYouGo contract that says, If you're on Virgin Mobile's legacy Pay As You Go service, there's an inactivity period of 180 days. You'll need to make a chargeable phone call or text message at least once during this period.

First of all, I’d check whether the problem with your provider was a temporary blip out of their control, eg bad weather or similar. I wouldn’t change unless it was a regular problem, tbh.

Nowadays you can ‘port’ your current phone number to a new provider, so if you do decide to change, that won’t be a problem.