Why didn’t Russia take part in the Versailles Conference?

1. Soviet Russia withdrew from the war in 1918, having concluded a separate Brest-Litovsk peace with Germany. As a result, Russia turned out to be a defeated country, unlike other Entente countries
2. Soviet Russia for ideological reasons could not, in the opinion of the Entente countries, participate in the post-war world order
3. There was a civil war in Russia and none of the governments was generally recognized at that time.