Like Facebook,Also WhatsApp has the option to block people you don't like
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To see this list, first of all you have to go to WhatsApp settings
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Then there you will see privacy option on everyone, click on it
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If you want to unblock someone, you can do that from now on. Tap on the contact in the block list to unblock it
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Then there you will see privacy option on everyone, click on it
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And if you go to this privacy option, you will see that the second option from the last side is blocked contacts
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Now click on block contacts and the list of blocked contacts will open .If you want to unblock someone, you can do that from now on. Tap on the contact in the block list to unblock it
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This block list option is one of the great and essential features of WhatsApp