Why can't I form more unions?

[German Conqueror 9]

I have made a union with Turkey and made Syria-Turkey from it. I now have 100+ relations with Russia and I also have an alliance with Russia. I keep sending "Form Union" and Russia always denies the option. How can I get Russia to accept the Union? And to note that I am number 1 on the global ranks. Please and thank you.

[LAUELCOMMIE☭ 41]

Hello, yeah, do not. NO!

Is too weard/wird/waerd what's this to do pass in the game, is too improbable