Show comments default if there is comment if not remove the space of the comment

Hi Everyone,

 am trying to show the comments history in a card layout to fetch the approval of the stage/comments added by the user /name.

Requirement is to show the comments if user is added, if not need to remove the space of the comment.  Below is my code and condition seems not working..

Thanks to help here and to learn more!

local!isCommentAvailable: a!isNotNullOrEmpty(index(ri!audit['recordType!{77342a51-f497-4d5d-a8e5-d123d13967df}TMA Audit.relationships.{683d367a-af56-4cf5-af48-16fbd40c5dbb}tmaComments.fields.{719d7da1-f969-4e01-85ad-d4ffb6f37778}comments'],1,null)),