Have tried the approaches already suggested - can't seem to use carrdav/caldav links to retrieve
I can see my lost contacts on bt email and saved in a folder - don't know how to load these on my iPhone - can anyone help?
Have a look at these links to see if they help.
If your email app has the correct settings for the BT servers do not delete your email account and try to set it up again.
https://www.bt.com/help/email/we-ve-updated-your-email
https://www.bt.com/help/email/updating-your-bt-email-settings