Lyrics - When I try to insert an "a" under a note, nothing appear

When I try to enter lyrics under a note, MusiScore does not bring up some letters. For example, I click on a note and try to enter the word "Avant". Well, the software should not appear "A".

Even if I enter any other letter, the "a" never appears. I have to open a text software and write the words taht content an "a" and then copy / paste in MuseScore.