Well, It happen, because everybody using adsense don't know each and every thing about adsense rules and regulations, and they inadvertently do those things that are strictly prohibited in adsense program, but yeh! it can not be denied. In some cases, adsense team banned the account for no reason or because of someone's click bombing.
Finance niche site are one the highest CPC site, but your site does not have content so it impossible to earn from that site. Add content, drive traffic to it you will earn a lot.