No signal has left me stranded

[Help_me]

Please help - the O2 service is constantly cutting out. It has left me stranded!! It says no sim and I've had to restart my phone ten times in the past few days. It happens WHEREVER I GO - not just at home so that service checker thing isn't helping!

I've also missed really important phone calls due to note knowing the service has gone again, I really can't cope with this.

Stressed.com

[MI5]

@Help_me 

Call into an O2 store, if you have one nearby, and they will supply you with a new sim and activate it for you. Be sure to bring identification with you.
Alternatively, speak to customer service. Use Skype if you have no other phone to use: Guide: A Guide to Skype
Call 0344 809 0202, 0800 902 0217 or 0800 032 1402
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 (https://o2uk.co/O2CTW), or Instagram (https://o2uk.co/O2CIG)

[Help_me]

Hi! Thank you for your response - I was using the sim card already for about a month before this all started happening? So does the above still apply?

[MI5]

Yes @Help_me 

It's the first thing to try.