Skill display no data, only variable names, second time around

I am facing a strange issue.

  • Simple Question-Answer Quiz,connecting to Google Sheet.
  • 3 rows of data
  • Display the question and answer (3 questions and 3 answers). Works fine.(screenshot 1)
  • Once the 3 rows are done, I am returning to Main Menu to restart the Launch Intent
  • Here is where the strange problem occurs - The page displays only the variable name. No content. But Speak is working. That means the data is being pulled from the Sheet. But somehow is not getting displayed (screenshot 2)

Here is the VF Project LInk.

The corresponding Google Sheet Data is as follows:

              Question                            Answer
      ________________________________________   _______________________
Row 1 Elvis Presley passed away in which year?   1977           
      ________________________________________   _______________________
Row 2 What was Jimi Hendrix's real name?         James Marshall Hendrix
      ________________________________________   _______________________
Row 3 Michael Jackson known as the King of Pop. 
      Who is considered as the Queen of Pop?     Madonna
      ________________________________________   _______________________

And to verify if this problem happens with other CMS/Databases, I tried with the following:

So only happens with Google Sheets. Even if I create an entirely new flow, the Display Data shows only variable names. No content.