If after changing the text of the Mailing List instead of the sender name you see !A or !R

If, when writing the automatic replies for the Mailing List, you use the special characters !A and !R, so that they are interpreted correctly by the Mailing List manager you need to place them in separate lines as a single character.
 
For example:
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Hello !A you are registered à NOT CORRECT

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Hello
!A
You are registered à CORRECT
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