OJS upgrade problem 3.0.2 to 3.1.1.2-2

Software Support
1

HI all,
I got this error message when running my upgrade.
"You are trying to downgrade the product “pdfJsViewer” from version [1.0.1.0] to version [1.0.0.0]. Downgrades are not supported "

Does anyone come across this issue?
thanks
-PT