Getting error for choose tag " Message= Error in element 'choose' on line 21, column 10: Too many characters in character literal"

I am getting error while publishing apim policy from pipeline

[Code= ValidationError, Message= Error in element 'choose' on line 21, column 10: Too many characters in character literal, Target= choose]

i verified everything looks good in tag and content of when

Start with the APIM policy and pipeline publication step that produces the validation error, focusing on the choose element and its when content around line 21. No repository file or test is named; the issue is done when the policy publishes without the character-literal validation error.

Written by the indexing model from the issue text.