Also for everyone else, there’s a lot of things that can cause problems with ads. In addition, people forget that campaigns might be limited in your area. You can only see ads a certain amount of times a day/week/month/max…so once you hit the maximum for any of those, you can’t see ads from the campaign again.
It is possible and plausible to hit those caps and then see no ads for a while. We’re not promised an unlimited stream of ads or money. We get them while they are there, that’s it.
If you need more details on how things work or what to watch out for that might interfere with ads, a good place to start is my FAQ at PSA: User FAQ - Support & Answers