To block another user, simply do the following:
Go to the profile of respective user
Hover to the three dots displayed next to their username
Click on the button ‘Block user’
Click ‘OK’ if you are sure you want to continue
You should see a pop-up that confirms that the user is now blocked
You can also block user using the chat feature. Just go in the conversation you had with the user you want to block, click on the three dots in the upper right corner of the chat window, and click ‘Block user’.