Conqueror not summon after killed sirus with other character

I used the first character to run the map to summon a conqueror, but I switched to the second character to kill sirus (This is the second sirus kill) and after the kill I switched back to the first character to run the map as usual. After running atlas again around 7-8 maps (tier 14-16), the conqueror didn't summon at all.

I searched for a solution from various places and tried to follow and still couldn't summon a conqueror
- remove the watchstones and put it back in.
- log-out & log-in again
- swap hideout
- move to other regions
- run low map tier (tier 1&3) to reset it before put the watchstones agian

before I opened the atlas, there was no warning message saying the map level was too low. and checked the requirement to summon a conqueror by using 4 watchstones which i put all 4 of them every time i run the map or switched to other zones.

Is it a bug? or how can I do?

After Sirus it's rng if conqueror spawns or not.
Just keep running maps, they should spawn eventually