Bug in Google AdSense

I had Google AdSense running on Health Care blog for a long time. What I didn’t notice was that it wasn’t making any revenue despite the traffic, and displaying AdSense ads. It wasn’t even showing the page impressions, not just not regular channels but also on url channel for the blog!

I found that it contained old style AdSense codes. I changed them yesterday and immediately the page impressions started flowing as well as the revenue.

Has Google discontinued old ad code?

They were making profits from my site without compensating me. It definitely looks like a serious AdSense bug.

Have you faced such problems with Google AdSense on your site?