How does Apple iPhoneSE close the message read receipt?

How does Apple iPhoneSE close the message read receipt? After the same iPhone user sent us a message, we found that when we finished reading the message, the other party's information list would automatically show the message we had read. What's going on here? The following small series will teach you the tutorial of reading the receipt of Apple iPhone off message.

First, we open the settings, and then look for information. After opening, let's close the ellipse to the right of the column that sends the read receipt on the left. (as shown in the figure below)