Inbound callers cannot hear me

[Draeths]

I believe since transferring from Virgin, inbound callers cannot hear me. WhatsApp inbound callers can hear me and if I make an outbound call, we can chat normally on both network and WhatsApp.

I have tried with my cover both on and off, resetting the phone, and it's up to date.

My phone is an Android, Oppo Find x2 Neo

[MI5]

@Draeths 

Did you get an O2 sim card yet?

If not, pop into any O2 store for a free swap.

Take photo ID with you.

[Draeths]

No, I have not received an O2 SIM. I assumed (clearly incorrectly) that everything would work after the transfer. Seems an odd problem considering everything else is working but will try that and update the post.

[Draeths · Accepted solution]

The SIM card change didn't resolve the issue on its own. I called customer services on the advice of the staff member and they needed to activate something their side. Once this was done a network reset and restart of the phone resolved the issue.
Thank you @MI5 for pushing me in the right direction.