Last OSX update, Catalina, changed permissions of your computer so LongoMatch might not work after the update. To privide permissions does not work, so until we launch a new release of LongoMatch you should open LongoMatch using the terminal. 


To do so LongoMatch first has to be closed. Use the searching tool and open the terminal. Then, copy and paste the next command and click on enter:

/Applications/LongoMatch.app/Contents/MacOS/LongoMatch