USPS not showing First Class shipping rates for small items

[andilyn]

I'm using USPS 2014-1030-K6 and no matter what I do I can't get First Class shipping rate to show up for smaller items. I sell a lot of lip balms and small jewelry items and the lowest rate that gets shown is for flat rate padded envelopes not First Class or flat rate small boxes which would be cheaper. Please Help! www.cherrypitcrafts.com

[mc12345678]

What weights are applied to the items? Certain options do not show as available if the associated weight is outside certain ranges.