First, you have to save their number then see their details on that phone you have blocked him/her. And in detail, you can find the block option. From there, unblock them. Alternatively, download TrueCaller, and after registering, open the app, find that contact you have blocked, open that contact in the app, and see in their profile. If they are blocked, then unblock them. Else, it's blocked from the main contact app.
Otherwise, steps to block or unblock a phone number on your Samsung Galaxy S series
- From the home screen, tap Phone.
- Tap MORE.
- Tap Settings.
- Tap Call blocking.
- Tap Block list.
There are three methods for adding a phone number to the block list.
- Enter the phone number manually.
- Enter the phone number.
- Tap the green + icon.
- Select a phone number from the call log.
- Tap LOG.
- Tap the phone number.
- Tap the green + icon.
- Select a phone number from the contact list.
- Tap CONTACTS.
- Tap the phone number.
- Tap the green + icon.