Dear all,
the problem is fixed - and it works fine:
the processing of the filed field content was done with the api call ivy.html.GET.
![alt text][1]
After changing this to ivy.html.GETOBJECT the Task notification mail is ok.
![alt text][2]
Thank you for the excellent support.
Best regards
Dieter
[1]: https://answers.axonivy.com/upfiles/Solution.jpg
[2]: https://answers.axonivy.com/upfiles/TaskMail.jpg