New seller doing FBM,Buy Box Issue

Hello everyone,so i am a new seller,I listed some FBM items about more than a week ago with good sales rank and there are no FBA sellers on that ASINs,even being with the lowest priceI don’t get the buy box while another new seller is having it and some of them listed after me,I haven’t even got a single sale in past three days(got 2 total sales on 3 out of 14 items in earlier 4-5 days),what am i doing wrong,should i apply automated pricing,if yes then which things should I consider in automating price,any suggestions would be greatly appreciated,thanks