“Invalid index: Cannot index property ’’identifier’’ of type String into type List of Variant

A Score Level 1

Expression evaluation error [evaluation ID = H0IAIER6]

in rule 'apac_getidentifiersforexcelreport'

(called by rules 'apac_sgp_importrqstlogrptdisplay' > 'apac_sgp_reportsdashboard'): “Invalid index: Cannot index property ’’identifier’’ of type String into type List of Variant

Can someone guide where to proceed with this defect ?

this errro comes in reports 

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