Can't delete blank frame in timeline

I had a chapter marker that dissappeared from the timeline.

It was still in the index and I could navigate to it by clicking it in the Index.

I tried to open it from the index to delete it in the timeline.. it would not open. I could not delete it in the index either.

When I navigate to the place where the chapter marker is missing there was a single frame clip. I deleted it.

Now there is a blank frame with no clip. It does not close when I try to drag the neighboring clips. It does not delete because it's blank, nothing to select

When I play past this blank frame the clip after it runs audio with nothing in the viewer.

I've restarted the app. no luck.

Any ideas?