How to remove the envelope label that appears on the TV screen?

Press the F4 button on the remote control, and the word "mailbox" will appear at the top of the button. When this button is pressed, a list of letters will be displayed on the screen. Select an unread letter, press the OK button to open it, then you can read it, and then press the Exit button twice (or the Back button, I can't remember clearly) to return to the TV program. Note: You must open all unread letters before you can remove the envelope icon. I was the first to answer, so give me a score! ! ! Thank you!