Need to make bathing suit/bra alterations… Sewing Machines Parts and Sales in Los Angeles

I bought a bathing suit that has a built-in bra with underwire. The rest of the suit fits perfectly, but the cups are beyond small on me and no matter how I adjust my breasts or tighten the straps I can’t get it to even look okay. I would return it for a bigger size, but I’ve already exceeded the time limit to exchange it. Does anyone have any idea what I should do?