How I can access in Actionscript the "text" property of a TLF text created in the Flash IDE

Question

I created a TLF Text with the Flash IDE in the main document.
I've assigned it an instance name with the IDE

When I try to access the text with Actionscript I cannot access the text field.
Of course if I transform in the IDE the text in classic dynamic text it works as expected

I feel very stupid and I suspect it has an obvious solution but I cannot find any info about the subject

// instance name is "myText"

trace(this.myText);
>> null

trace(this.getChildAt(0));    
>> [object Movie Clip]

trace(this.getChildbyName("myText"));
>> null