"You dont have an arbitrator selected" - yet i do. please help?

I am getting this message on half of single altcoin offers. For example Siacoin, in the picture. One offer i am seeing i can buy from, and the other is greyed out asking me for an arbitrator. Whats the deal with this?

This seems like the same error from this topic:

To quote Manfred:

So basically you can’t take that offer. The arbitrators for that offer are not available anymore.