Finding out who has blocked you on WhatsApp Messenger isn't an easy task, but here are some easily identifiable signs that can help you to confirm your suspicions. Please note that none of the methods described below are fail-proof; there may be any number of other meaningful reasons explaining why you are unable reach someone on WhatsApp.
How To Know If Someone Has Blocked You on WhatsApp
There are three tell tale signs that you have been blocked by another user on WhatsApp.
Read Receipts Aren't Displayed
The first sign is that the blue read receipt checkmarks are never displayed. WhatsApp use checkmarks to indicate the status of your sent messages. A single gray checkmark indicates that your message has been sent; a double gray checkmark indicates that your message has been sent and delivered; and a double blue checkmark indicates that your message has been read.If all messages sent to a particular contact have a single gray check mark, it may be an indication that you have been blocked.
It should be noted that WhatsApp only displays checkmarks when the Read Receipts feature is enabled on your smartphone. In addition, as WhatsApp requires an internet connection (via mobile data or WiFi) to send messages, if one of you is disconnected from a network, your messages cannot be delivered.
Status Updates Aren't Visible
If you no longer have access to information such as the last seen or online status of a contact, one of two things is possible: your contact has either changed their privacy settings, or you have been blocked.
The same applies to the profile picture of the person. When someone blocks you, any updates made to their profile picture will not be visible.
Unable to Join a Contact or Group
One fairly obvious sign that you have been blocked by a contact is an inability to invite this contact to join conversations or groups you manage (as an administrator). Any attempt to contact a user who has blocked you will be met with an error message.