Can't slide tracks in timeline

[urbanl28974291]

I've seen several posts similar to mine, but none of the suggestiosn given there have helped me.

I was merrily and successfully working on a Premiere Pro project a month ago.  I needed to take a break and got back to it this week.

When I did, however, I found that I couldn't use the Selection Tool in the Timeline to slide any of the tracks.  I'm getting a new response.  The cursur arrow turns to one with a black circle with a diagonal line (which I interpret as I can't do something) and then a new entitty pops up with Insert options.

I'm running on a Windows 10 0.18363 machine.

Did a recent change in either Windows or Premiere Pro cause this?

I see that some previous suggestions dealt with not tracking keyframes (which I don't).

Any idea of what I need to do to return to the "good old day" when I could edit my project?

Thanks!

[urbanl28974291]

I may have figured it out.

When I switched from Editing mode to Assembly mode, things behaved as I wanted them to.
I don't remember anything like this from the past, so I still wonder what changed.

Regardless, thanks for your time.

[Ann Bens]