Good Morning,
I am Concatenating several fields to create a unique id tag for my surveys. Part of that is a Start Date for the training session. When I write the Concat formula in XLSForms everything checks out and when I enter data on the Preview in Survey123 Connect the time shows up. After publishing the survey I go to the browser and open the survey. The Unique ID Tag fills in with the data I enter except for the time. It just says "Invalid Date". I have the time coded as format-date(${start_time),'%H:%M'). Below is the entire code. It is a mix of text and dates so Im guessing that could be an issue. Let me know.
'concat(string('TIMS'),' - ',${city},' - ',format-date(${training_date},'%m%d%Y'),' - ',format-date(${start_time},'%H:%M'))
Here is the return on the survey in the browser: