New SIM won't activate

[Will-44]

I have been a O2 customer since 2018 and started a contract last summer and I recently upgraded to a new phone last Friday, the SIM recognises that it is the O2 network but it won't activate to allow me to text or call.

I have tried to chat on MyO2 but can't go further as I don't know the security question and neither does my mother as she is the account holder due to myself not having the credit rating.

I can't receive calls from potential employers and I have to hope they'd email me, I can't even receive voicemails or a text.

So can someone help me?

[Will-44]

Went in store but needed my mother there as she is account holder and ID wasn't enough for security reasons and she can't make it till next week due to work so I was told it can be activated over the phone.

[Will-44]

I called up last night and was able to sort it out, SIM is now activated.

Thank you everyone for your time and help.

[MI5]

Good news @Will-44