Could you try adding an index based ordinal identifier for the same. Usually QTP follows a specified hierarchy of identification properties at the time of identification
Mandatory>Assistive>Smartfilter>Ordinal( Not sure as to where visual relationship identifiers come [img]/images/graemlins/smile.gif[/img] ).
Try the below two things :
1. Turn off smart identification & add index based ordinal identifier for this particular frame.
2. Go to visual relation identifier & just check if there are multiple objects with similar properties existing.