You need to contact O2 for a new eSim pack.
All numbers are in this guide Guide: Coronavirus Community Help and Support
Or 202 from your O2 mobile.
Advice from an O2 Guru to get through:
When you call 202, you will be asked for the reason you are calling.
Stay silent for 15 seconds and you will be taken to the keypad options.
Press 2 for Everything Else
Press 5 for More Options
Press 7 for Anything Else which will put you though to someone.
You can also try saying "Upgrade" or "Fraud" to be connected to an advisor.