Mistakes happen! We're happy to help. To unblock a profile all you need to do is:

iOS:
Go to My Profile > Settings (icon in the top, left-hand corner) > Tap on the Blocked Profiles option> Find the profile you want to unblock and tap the unblock button next to their name. A menu will then appear for you to be able to unblock that profile. Once you have unblocked them, they will be removed from the list.

Android:
"..." in the top, right-hand corner of your screen > Settings > Scroll down to Blocked Profiles > Find the profile you want to unblock and tap unblock.  A menu will then appear for you to be able to unblock that profile.