Click on the GlobalProtect icon in the menu bar, and then click the three lines in the upper right hand side of that drop down window, then click Settings: 

Next, click on your email address in the list of Portals, then click the "-" button in the lower left corner to delete. Choose Delete from the pop up window that appears:

Now click the red button in the upper left corner of that window to close it out. When you click on the Global Protect icon in the menu bar now, you will get a field to enter the correct portal address, Enter that (type it, don't copy/paste, as we've seen issues with copy/pasting into this app) and click Connect.