Offline sequence does not link to online clips

Hi there,
I have a sequence edited in a DR 17 project and imported the bin into another one (all settings the same, just project name was different).
Now all souce clips are online but the sequence itself is not. Right click on a clip in the sequence and - "find in media pool" does not work. Any idea how to link this sequence to its source again? Thanks!

Other weired things are happening!
To an offline sequence DR links randomly the same clip, althoug name, TC and everything else is different.

List out your steps.