No Access to Story-Dungeons

Game mode: Single-player
Type of issue: Bug
Server type: PvE
Region: Germany
Mods?: Yes

Bug Description:

It is impossible for me to enter any dungon for the story. I have tried to enter Skulker’s End, which does not work, and in the Ruins of Xullan the door to Boss remains locked. It will not open. In the Volcano, the Snake King’s Tron is empty. No boss is created.

Expected Behavior:

The bosses should be created and I want to enter the dungeons.

Installed Mods:


Steps to Reproduce:

Attempt to enter a boss room or reach a boss.

I have now tried again to go into various other dungeons and areas with boossen. There is not a single place where a boss enemy spawns. I wanted to get Shadow Blossoms, but that didn’t work either - because there was no boss in the arena. I could only port out of the areall. Currentlyl the complete story for single-pllayer is broken.
Does anyone here read this at all?