Google Auto Ads. Lowest CTR- What to do?

Hi guys. I have a little site with little crowd. Most of the traffic is from US or UK. But my issue is that the RPM and CPC is pretty depressing. I just want to know what can i do about this. I have enabled auto ads. Most of the traffic is from mobile search. So any advice?

What country is the Adsense... Cause I've noticed cpc differs by country of origin of the Adsense account.
E.g on a US Adsense account, I get $1 to $2 cpc
But on a Nigerian Adsense and same traffic with the Us Adsense I can barely get up to $0.17 cents