Master timeline doesn´t affect slides

Hi everyone,

I would like to delay the entrance of a text. I do it on my master...

... but this doesn´t affect my new slide:

 

Adding this textbox in a new layer on my master (and its coresponding trigger) is not a solution because I need to type different content on different slides, and this way the textbox doesn´t even appear on the new slide, so I can´t type anything.

Is there a solution that could avoid me to move the text along the timeline on every single slide I create?

Thanks in advance,

Edu.