@Brett13
Start by rebooting the phone.
If that doesn't work, you may have to back up and factory reset.
Knowing what phone and what you updated will help us too.
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion.
This is not Customer Service so we are unable to help with account specific issues.Currently using:
Pixel 7a (O2 & Lyca), One Plus 6 (Sfr), iPhone 12 Pro Max (Vodafone)