System Tag Current Screen Name implement error in Runtime.

[bpe]

I've added a "Current Screen Name" text on various views.
The text Value is set to the SystemTagCurrentScreenName, which is added as a system tag (see attached screen dump).
When running the project in Runtime I get the error message, as shown on the attached screen dump.
If SystemTagCurrentScreenName is removed from the text Value, I don't get any error messages.

In another project it's working fine?!?

What could be the difference between the two projects?
They are both made in iX Developer 1.31.93 and are iX Panel T7A.

[bpe]

Problem solved

The text object was copied from another iX Developer project, and for some reason it didn't work in this project.

I deleted the copied text object and inserted a new text object, which is set up exactly as the copied text object.
The new text object works, and shows the current screen name, using the system tag "SystemTagCurrentScreenName".