Check if wx is installed twice
ls -l /usr/bin/wx* ls -l /usr/local/bin/wx*
Only one of the two commands should give results. If none gives results (something like "No such file or directory") then you don't have wx installed at all. If both give some result, then you have wx installed twice. In this latter case, read How to uninstall wxWidgets to remove all wx installations and install wx again.