Text Height in the Textstyle

Good morning,

I have this strange problem, also on the Draftsight example drawing:

I create 2 different textstyle, for example Standard10 with the text height of 10

and Standard20 with the text height of 20.

I insert a text, I see that the height is 2.5 (where come from?).

Then I select the created text and I change the textstyle

between Standard10 and Standard20, it doesn't change the text height!!!

Somebody has the same problem?

How to solve?

 

Thank you

Ivan