Know if Someone Blocked You on Facebook Messenger

This wikiHow teaches you how to find out if you've been blocked by someone on Facebook Messenger has blocked you.

Steps

Open Facebook Messenger. Look for the blue chat bubble icon containing a white lightning bolt. It should be on your home screen, or in the app drawer if you’re using an Android.
Type your friend’s name into the search box. It’s at the top of the screen. A list of names that match what you’ve typed will appear.
Tap your friend’s name in the search results. This opens a chat with that person.
Type a message into the text box. It’s at the bottom of the chat.
Tap the send icon. It looks like a paper airplane. If you are blocked, you will see a pop-up message that says, “This person isn’t available right now.”

Navigate to https://www.messenger.com. You can use any web browser to access Facebook Messenger on your computer.
Sign in to your account. If you’re already signed in, you’ll see a list of recent conversations. If not, click Continue as (your name) or type your login information as prompted.
Type the person’s name into the search box. It’s at the top-left corner of the screen. As you type, a list of contacts will appear.
Click the peson's name in the search results. This opens a chat with that person.
Type a message into the text box. It’s at the bottom of the screen.
Press ↵ Enter or ⏎ Return. If you are blocked, you will see a message in the chat box (where you just typed) that says “This person isn’t available right now.”