Open Cross Section Model doesn't work in heads-up prompt.

I have a dgn that has a few corridors in it but one corridor isn't acting like the others with regards to the heads-up prompt.  So I hover over the corridor to bring up the corridor prompt and try to select the Open Cross Section Model but nothing happens.  What could be causing this?  I can still open the cross section model by using the tool on the tool box but not the heads-up prompt.  I noticed that when I select the corridor and look at the element information it looks like this:

But the other corridors in the file look like this:

Does this mean that the corridor is corrupt?  Any ideas on fixing this or understanding what is going on would be helpful.  Other tools like corridor Objects and reports aren't working either on the heads-up prompt.