Now, if you have fallen, the simplest way to act is to delete the problematic message. If you have an open WhatsApp Web session (in a computer browser) or through the official app on your PC, simply delete the content.
iPhone: In the conversation list, drag the conversation with the unknown number to the left, select “more” and you will be able to block and report that contact.
Android: In the conversation list, press and hold the conversation with the unknown number, and select the lock icon at the top. In the pop-up, you can block and report this contact.
Take advantage and, if it’s a contact you don’t know, block them and change your group privacy so that only contacts can add you to groups.
If it didn’t work, try closing the app and opening it again.
iPhone: on the home screen, swipe up from the bottom of the screen and stop in the middle of the screen; Swipe sideways (left or right) and find the app you want to close. Finally, slide your finger up on it. On models with a home button, like the iPhone SE, just double-tap it and drag the app you want to close up.
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