Hello Drisya,
that likely indicates that some of the prerequisites from Note #1717357 are not met: if the menu "Export as PDF" does not even appear, I would say the corrections mentioned in this Note are not yet implemented.
(In some previous cases I have seen that "Export as PDF" appeared but grayed out - in this case either the SAPGUI version was low or the menu needed to be reactivated. Anyway, both symptoms show prerequisite-problems.)
Best regards,
Laszlo