The WhatsApp icon looks like a green box with a white speech balloon and a telephone icon in it.
 This is your Menu button, and it will give you options to open a New group, start a New broadcast, open WhatsApp Web, your Starred messages, and Settings.
, This option has a key icon next to it. It will open your account settings.
, This option will show you the number of contacts you have blocked, and tapping on it will open up a list of all blocked contacts.
, This person will now be able to call you and send you messages on WhatsApp.
Open WhatsApp Messenger.
Tap the ⁝ button in the upper-right corner of your screen.
Tap Settings at the bottom of the menu.

,
Tap Account.
Tap Privacy.

,
Tap Blocked contacts under the Messaging heading.
Tap on the name of the contact you want to unblock.

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Tap Unblock <Contact Name> in the pop-up.
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