Since Android interfaces vary by manufacturer (Samsung, Google Pixel, Motorola, etc.), the wording may differ slightly, but the general process remains consistent.
This is best if you remember the specific number or name you want to unblock. how do i unblock a number
You can also find the same "Blocked Contacts" menu under the Messages or FaceTime tabs in your main Settings app. How to Unblock a Number on Android the wording may differ slightly