I just released a game and it got flagged for this same issue, however I didn’t find out about it until after contacting ad support. The game is currently featured on the front page of the App Store in a few countries, and I’m incredibly disappointed that ads aren’t working. I use Unity Ads in my other games but this is the first hiccup and it came at the worst possible time. I’ve submitted the appeal form (#1812846) and am eagerly awaiting a response.
Contacting support is useless, friend, I was also blocked citing a duty block allegedly for fraud, I wrote to support but it feels like there is no support. This is a massive problem with Unity in blocking developers, they don’t care about us.