A few weeks ago, I noticed that both of my ads in the old Ads Manager did not run at all. I suspect that because I had another ad running in the new Ads Manager, it temporarily made my ads in the old Ads Manager unavailable.
Extra details:
In the first picture, you can that the first 2 ads did not run. The 3rd ad is another one I created because I found it strange that the others weren’t running, so I turned off all the others to test it.
The third picture shows an ad that I created using the new Ads Manager. It appears as “off” in the picture, but it was actually on before I took the screenshot. I was testing whether turning it off and on would make a difference, but it did not.
From what I have observed, the bug occurs whenever you have one ad created in the new Ads Manager and one in the old Ads Manager at the same time.