Open the Phone app
Tap the three-dot menu or More
Tap Settings
Tap Blocked numbers or Block numbers
Find the number you want to unblock
Tap the X, Remove, or Unblock option next to the number
Confirm if prompted
Open the Contacts app if the number was blocked there
Select the contact
Tap the three-dot menu
Tap Unblock contact
Open Messages if the number was blocked in texting
Open the conversation
Tap the contact name or menu
Tap Unblock
Check your call or spam blocking app if you used one
Remove the number from that app’s blocked list