Stop People from Adding you to WhatsApp Groups
First, make sure you have the right version of WhatsApp installed. The beta program run by WhatsApp releases features before officially rolling it out. You can enroll in the beta program to receive future updates by clicking this link and installing the WhatsApp beta version.
Read: How to send WhatsApp Messages without saving contact
Update WhatsApp on your Phone to the latest version(2.91.93 or higher). Go to Settings by tapping the options(⋮) icon on the top right corner to open the drop-down menu.
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Open the Account Settings page by tapping 'Account'. Select 'Privacy' from the list of options.
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Under Privacy Settings, look for Groups. If you can't see the option in the list then you may have to wait for WhatsApp to push another update. Go to groups by tapping the option and you'll see three options, just like Status, Display Picture, and About. You can select from Everyone, My contacts, and Nobody who can add you to a group.
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Must Read: Enable Touch ID and Face ID on WhatsApp
Now, no one would be able to add you to a group without your consent. Whenever they try to add you to a group, they'll receive an error message shown below.
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