I have recently upgraded to full fibre and digital voice.
I had call guardian which used to work properly.
Since upgrading it no longer works, every call is screened. I have even copied over my contacts onto the new alexa handset I got as part of the upgrade
Any ideas how to fix this greatly appreciated?
You need to enable caller display via MyBT. Manage your Digital Voice Options.
https://www.bt.com/help/landline/digital-voice--how-do-i-use-my-calling-features-
I assume you have plugged your existing phone system, which has Call Guardian, into the socket on the back of the Smart Hub 2?
Remember, Call Guardian is a feature of your existing phones, and will not work with the new BT phones.
You may also find this thread helpful https://community.bt.com/t5/Home-phone-including-Digital/Re-BT-FTTP-Digital-Voice-and-BT8500-Call-Gu...