Thanks Juma.
The issue is because you have three questions, with Names:
- example
- kartoshka
- example2
The 'instance_name' in the settings sheet is referencing a question with name 'example1'
- concat('Label1: ',${example1},' Label2: ',${example2})
As 'example1' does not exist, it throws an error during construction.
Also just noticed you've posted this in Python. Please move the thread to the Survey123 community for more visibility.
Cheers,
Chris