FDC from Taiwan／FDC du Taiwan

Cover to South Ossetia, return from Georiga.
l'enveloppe à Ossétie du Sud, revenez de Géorgie.

2008(97).12.15：Send from Taipei, To South Ossetia
(Хуссар Ирыстон; Южная Осетия), Via Russia→
29.12.08.16：Arrived Vladikavkaz (Владикавка́з), North Ossetia→
07.01.09.13：Cannot enter South Ossetia, left Vladikavkaz to Georiga.→
22.01.2009：Write "Force Major", return from Georiga→
2.2.09-11：Arrived Taipei
There is censor open on the left side of cover.

PS: This is third time I send to South Ossetia and also third time cannot
enter, Could anyone can explain "Force Major" mean?