Wrong display name and icon in launcher

Solution 1:

Either in /usr/share/applications or ~/.local/share/applications, a "left over" .desktop file must be left behind.

Remove the duplicate desktop file(s), log out and back in and it should be fixed. If you are having doubts on which is the right one to remove: .desktop files show their icon once you make them executable. You can also look inside the file (drag it over an opened gedit window).

File- names of the .desktop files can be confusing, since the name you see in Dash can (and will) be different from the name in Dash; in Dash, you see the name, defined in the Name= line of the file.

Related: https://askubuntu.com/a/516346/72216