Getting an error "Attribute Master detail has duplicate values" (item matrix addon)

Getting an error "Attribute Master detail has duplicate values" (item matrix addon)

Problem:

Getting an error "Attribute Master detail has duplicate values" while trying to import child items in bulk for existing parent code.

Solution:
Please try importing the data using the attached Template or as shown below:
RecordNumItem GroupParent Item codeParent Item Name2D Grid ItemGENDERBRANDSEASONCOLOURMATERIALPACKErrorMessage
1










2