HELP!!! Stretch marks!!!

Jayla • Jayla💕 21. Happily taken ❤️
Someone please help me!! 
I have stretch marks under my butt, I'm not overweight at all. I'm 5'5 and 120 lbs, I just have random stretch marks. And they're driving me crazy! Especially with summer coming, I really want to wear my bathing suit. Someone please tell me how to get rid of them!!!!