How do I fix typewriter ?

Hi !

I am actually making a game where there are dialogs. before, I display the text using left(), but when I try to change it for use the typeweriter feature, it literally dosen't work, and I don't know why 🤔

Here is an image of my code :

What does the action you use to call this function look like?

Here is the code, I check and every thing work if I replace Typewriter text by set text