Survey won't submit , after applying a method to restrict duplicates choices in a repeated group

hello, this is my first post here and i’m stuck at my final step in my form building

i have made a select one question that is imported from a CSV file which contains names i want a method that restrict the enumerator to select the name again from the list in the repeated group ,so far it works but when i submit the survey it brings me back to the second repeated group and tells me that the answer is invalid, i can’t see where i have gone wrong can you please take a look
the calculations for the subject start at row 92 and highlighted in green

Maybe it would be easy for the community to support if you share with the community the section that is not working at your end.