Based on emails we have recieved from you all, we were able to figure out that issue was either not reproducible or that the feature was not being used correctly.
Closing this issue was for now. Let us know in case you encounter the issue again
An error occurred while saving the commentMarm commented
It's definitely a bug with the latest CC version. Was working fine until I updated my app earlier this week. Character styles are set, even switched the language just to test it. Mine is not working at all, as if the spell check never even scans the document.