Although Messenger is currently a standalone application for mobile devices, both accounts are also in sync, so that everything that happens on one social network happens on the other. Like the stories you share, the users you've added to yours friends list or the ones you blocked or decided to ignore, etc.
Why is my message not reaching a Messenger user
It can be due to various reasons. Remember that in this application in order for the receiving person to see the messages you send, they must agree and accept your request to start a conversation.
If we have never sent a message to that person, it is very likely that it will not be delivered or it will take some time to do so. However, if you urgently need to communicate with that person, you should try other methods.
You can try, for example, to send him one friend request or to comment on a post that he created on his profile or on a group or Facebook page. It is a good alternative to get her attention, as this way she will have a notification warning her that you are trying to communicate with her.
Remember that although Messenger is an application that has decided to proceed on its own, it is Facebook's messaging service and therefore are accounts that are synchronized.
Why are my Messenger messages not being delivered?
Sometimes you try to send a message to someone you have added to your friends list or have already started a conversation before and it doesn't get delivered.
This can be due to several reasons that relate to the recipient of the message: they have blocked you from their account, they have ignored your messages, they have logged out or they no longer have you on their friends list. Let's see the first reason: the other person blocked you. For this reason we will not even be able to send a message.
If this is the case, you will have a caption in the chat " You cannot send or receive messages from this person " or "That person is not receiving messages from you right now" will depend on the device you are using.
The second reason: ignored your messages. It may happen that the other person simply decided to ignore your messages, so they won't even appear as delivered on your device.
To find out if this is the case, you should pay attention to some details such as: figure «Active», ie connected or using the app, you can see it under the username; and the sign of tick that you have on the right of each message has a white circle, that is, he did not receive them.
If the message has been delivered, it will have a blue circle and the check mark will be white. That is, the inverted colors. If they've also seen your message, you'll see the word "Viewed" under the last message you sent.
If he has decided to ignore your messages, they will be sent to "Message requests" and will not have a notification telling him that you want to communicate with him.
The other person is not connected. If the other person does not have the Facebook Messenger app on their mobile and their account is closed, the its state will be inactive and messages will not be delivered. Here you just have to be patient and wait for it to connect so it can see your messages.
Another reason could be, as previously mentioned, that you are not more on their friends list. Maybe the other person has already passed you and decided to remove him from the contact list. In this case, your messages will be sent to the spam folder and the receiving person will not have a notification to inform them of your message.
If the Messenger messages I send aren't delivered, it's because the recipient has to accept your message request to start a conversation.