Trouble with updates in Zorin 9 core
 

All my updates fail to install in Zorin 9, I found that under the Update tag in Software and Update, none of the boxes are checked, and the system will not allow me to check them, I try to check a box, then the Authorization box pops up, I type in my password and click on Authorize, it and the checked box then disappears. Any help appreciated, PS I'm a newbie and would find dealing with terminal commands over my head, maybe... Thanks....I can always re-install Zorin, but...