Dynamic Stamp asks only once per Document for information

Hello all,

I'm creating some dynamic stamps in Acrobat. There are no problems with displaying dates, identities etc.

But now I'm trying zu create a stamp that asks the user to enter a number that shall be displayed in the stamp. This stamp works great - but only when I use it in a PDF-document for the first time. When I use it again in the same document, I can not enter another number - it automaticly displays the number I entered without asking again. No chance if I delete the first stamp either. It still remembers the number I entered before. If i use the stamp in another PDF-document, it starts again: First use: I can enter the number. If I use it again ... no chance ... *grrr*

I'm using this bit of code in Acrobat Pro DC (2020.009.20067), German:

var cAsk = "Enter number: ";

var cTitle = "xxx";

if(event.source.forReal && (event.source.stampName == "#stampname"))

{

                event.value = app.response(cAsk, cTitle);

}

What's my fault? Could anybody give me a hand? I'd really appreciate it!

Hannes