"Form Union" limit?

[Puppy1305 0]

So i did a muscovy game in the 1440 start. Built a huge army. Demand vassal a few more people to add to my collection. 

Didn't want to demand annexation cos it feels cheesy and not really historically fun. So i improved relations with all vassals and one by one i unipned all of them to create the glorious nation of "Muscovy-Rostov-Yaroslavl-bellozero" with a flag that looked equally horrendous as the name. 

After this all my vassals regardless of size never wanted to union with my. I at the time thought it was an issue with my flag being to crowded and the game going NOPE. So i formed the russian empure to reset flag and tried again but it never let me. Is anyone else getting this issue? 

I did also have the same issue when playing as the pope. After forming unipns with 3 nations i never could again and had to do the cheesy demand annexation. 

Thank you for reading! 

[143609 9]

I always get rejected if i want to create union with other civilizations when i'm a union already.