Parameter 'abc' in file (fileType DECLARATION) file: [ File path 1 ] was previously declared in file: [ File Path 2 ] (fileType DECLARATION).
Single Parameter has been declared twice. It could have been declared multiple times in a single file or multiple files.
It could be that the whole file has been duplicated at 2 different location like src/mail/resources and test/main/resources
Make sure that the parameter has been declared once. Remove Duplicate entries.