What does this message mean when doing a vaildation?

Tiomasai

After running a validation, I get a message "Corrected 23 Bought or Shares Added transactions that were incorrectly categorized as a realized gain. If any of these should have been for a Cover Short Sale, you should modify them."

What does this mean? I have only gotten them since I had a change in my 401k retirement account but not sure what to do, if I have to do anything and if so, how to correct it. Any help you can provide is greatly appreciated.