I'm running a handful of mobile sites hosting AdSense for mobile ads.

The sites are content sites and collect leads for clients in insurance and financial services.

I bought display advertising from major mobile ad networks to drive traffic to my site, and started getting a lot of volume (and clicks).

Things were going very well on the lead side and AdSense side until out of the blue AdSense banned me.

Isn't it possible to buy traffic? If so, why might I get banned? The sites were otherwise TOS-compliant in all respects.

I've read the various posts here about getting reinstated... is there anything else to do in this case?

Thanks!