Why don’t my Facebook Advertising reports match my targeted interests?

If you are referring to Page Insights, which shows the demographics of individuals who liked your Page, perhaps you have a different audience on Facebook than you originally thought..

Another possibility, if you are targeting specific ages with your ads, and your ads have many Connections, then your Page demographics should shift to fit that targeted group. Again you would have to first displace the first population to shift that population, as its a ratio