If you made a GSX customization profile which you created BEFORE we added GSX L2 jetways to LSGG, you must remove it, because your own customizations will always have the highest priority so, if your file didn't specificy GSX L2 jetways, GSX will trust it and won't create any.
Remove any .INI file for LSGG in your %APPDATA%\Virtuali\GSX folder, so GSX will use the .INI file we provided for it in the fsdreamteam\LSGG\scenery folder, which surely contains GSX L2 jetways.
Of course, this assumes you have the latest GSX installed, which includes GSX and GSX L2 and, of course, this being an FSDT scenery, both GSX and L2 will always work here, regardless what you bought.