Anyone else have problems with the soft cup?

I don't know if it's because I might not have it in right or if I am to heavy but I feel like I leak more with te soft cup than with tampons. My periods are pretty bad where I to change my tampon every 90 minutes. The soft cup I feel is ever two hours. Do I bleed too much for the soft cup? I follow the instructions right and put it in right but still have to change it every two hours. I want to try the diva cup but don't want to spend the 30 on it if I have to clean it every couple hours. Opinions? Advice?