Table Match is not working

I have used DigDB for about 2 years now, quite successfully, to compare two tables and hide the matches.  Recently, every time that I attempt to use it for this purpose, it states that there are no matches, even though I can physically compare the data and see the matches.  I have tried verifying the data and making sure that the cells are formatted identically.  I am at a loss as to why the program no longer recognizes that the data contained is identical.