Are you logging in to your Canvas instance before clicking on the Commons link? As far as I know, that's always been a "gotcha" for us (in the USA) for Commons links. This may not be the issue you're having, but I figured I'd mention it just in case.
I'm in Australia and we have exactly the same issue. Being logged into our instance of Canvas does not help - I just get routed back to the instructure login (which is not useful).
The error is still not fixed. Apparently not enough people are having the problem. Getting a link to work shouldn't be much of a problem. I have also created a support case, but nothing happens.
Or do they not realise that they have this problem? We have no take-up of Commons because you cannot send a direct link to a resource. Who is going to go search for the resource? Such a waste of a product.
We are having the same issue as well. I have tried in our own instance and have asked colleagues in different districts too. All are having the same error even if they are logged in.
