Yes I got that- the error message I sent is an earlier one. So I changed it to look for .corr rather than .keys. Unfortunately, similar error comes up.
From my code : I do not really need the RT just the total count of their correct responses.
Hello Tin_Tin,
do you mind giving us a bigger picture by making your repository public and posting its link here?
Best wishes Jens
Hi Tin_Tin,
If I understand correctly, this should do the trick 
feedbackAfterBlock - forum.zip (8.4 KB)