Alegro Response:This style is a balconette bra, which is not a full coverage bra. It is open at the top and does not lift. You mentioned that you bought one size bigger, but didn't mention whether that was one cup size larger or band size larger. If you are an F, you would probably need a FF, which Alegro doesn't make in this style. We do carry other styles in FF that I'm sure you would like. Kimberley from Radisson
HerRoom Response: All your symptoms suggest you need to go up a cup size.
Alegro Response: This bra is a balconette, which is meant to run very low in the front. Alegro runs a little on the small side so you should go up a cup size on this bra. Lynn from Tx