How to reply to reviewer feedback in multi-stage abstract review process

Why does an author receive an error message about required fields when trying to submit a response to reviewers through the rebuttal option, and how can they properly submit their response?

If an author tries to submit a response to reviewer feedback via the rebuttal option but sees an error message stating that required fields (such as Abstract Title) must be filled, it means they are attempting to submit a new abstract rather than responding to existing reviewer comments.

 In this case, the correct procedure is for the author to edit the existing abstract where the reviewer feedback was received. 

Additionally, if multiple review stages are enabled, the author can only see and respond to feedback associated with the current review stage of their submission. If the feedback is from a previous review stage and the submission is currently in a later stage, the author will not see that feedback or the option to reply. 

Therefore, admins should ensure submissions are in the appropriate review stage for authors to access the relevant feedback and submit rebuttals.