Have you been muted of facebook is message is only sent not delivered

I am seriously confused with the new Facebook am I muted if the message is sent but not delivered! The previous message was delivered and not seen and then this message is not seen or delivered its just sent even tho the person is online on Facebook! May someone please answer this?
Asked May 27, 2015

TIP: If it's not your answer to this question, please click "Leave a Comment" button under the question to communicate with the question owner.