[1.21.d] disapearing city event after zone merge attempt

[kojusoki1]

Problem: "Demagouge in Drifthead" event disapears after I try (unsucesfully) to merge this zone with another

Description
1. Currently, there are 5 decisions waiting. one of them is the Demagouge in Drifthead.
2. I conqured 2 zones last turn (Drifthead and Siringa)
3. I have already appointed governors to these zones
4. i was trying to merge the Drifthead zone into my capital (Warsaw), however game doesn't allow me to do so (diffrent population type etc)
5. I click abort
6. Event "Demagouge in Drifthead" disapears

Savegame attached

[Vic]

Big thanks! Will be fixed upcoming! note that it was the truck station that prevented merge by the way.
best vic