Sim not working

[Amck]

My sim has been innactive since Saturday 

[Bambino]

@Amck This is not O2. This is a customer community. You need to speak to customer service.
Call 202 from your mobile or 0344 809 0202, 0800 902 0217 (Payment Management) or 0800 032 1402. Use Skype to call the 0800 numbers if you have no phone to use: Guide: A Guide to Skype 
When it comes to 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.
Say 'Upgrade', 'Lost/Stolen', or 'Fraud' if the suggestion above doesn't get you through.
Best time to call is 8 am.
You can also reach O2 via social media:
Facebook (https://o2uk.co/O2CFB), Twitter (now X) (https://o2uk.co/O2CTW), or Instagram (https://o2uk.co/O2CIG)

[MI5]

@Amck 

Check guides:

Guide: How can I sort out my network issues? 

Guide: Is the network down for me or everyone?