BT call potect 1572

I've been and blocked someone i don't want to block, is there a way to unblock them from the hand set please, i've gone through the menu but can't find a way to unblock some one, I had a scam call and i thought i'd do it later and a friend rang but i didn't know so i thought i now block the scamer but i didn't but blocked my friend insted
So how do we unblock people please?

 

Have you tried looking on youtube, I've never used any call blockers.

 

I've never used 1572, but Solved: Unblocking an incoming landline from Call Protect ... - BT Community

 

Thank you Nigel, i did read that but we don't have "My Bt" so we have phone them and yes around in circle's we go again

 

Well we spoke to a different person this morning and it seem's to be sorted, they stopped the 1572 service yesturday afternoon and the guy said he would ring back but he didn't hence we rang this morning and he restarted the service and i rang 1572 to see if it was working then i went the the junk voicemail to listen to any messages but there was any so i'm hoping that it all been cleared so my friend can ring me with out going to 1572 voicemail ie being blocked

So now i'll start blocking scam calls and not people i want to call
Also the guy i spoke to this morning said he wasn't happy and it shouldn't have happen that the guy yesturday didn't phone back and did i want to complain which i said no if the servise is working as he could have had a bad day and forgot