> I managed to get Google Ads suspended due to blocking Singapore

How did that happen, why? I feel like a lot of people here would not want to make the same mistake, so details would be very welcome.

As long as pages weren't being served and so there was never any case of requesting ads but never showing them, I don't understand why Ads would care?

Not the parent, but it sounds like they blocked the entire country, including Googlebot's Singaporean IP ranges.

If your server returns different content when Google crawls it compared to when normal users visit, they might suspect that you are trying to game the system. And yes, they do check from multiple locations with non-Googlebot user agents.

I'm not sure if showing an error page also counts as returning different content, but I guess the problem could be exacerbated by any content you include in the error page unless you're careful with the response code. Definitely don't make it too friendly. Whitelist important business partners.

If you run Google Ads for your customers or yourself and you through whatever means block the Google Adsbot it will come up as a "site unreachable" error and Google will suspend all your ads running. If you dig down further it will state some kind of DNS error as the problem. This is why blocking entire countries is problematic.