help?plz

so I've been over weight most my life but a couple years ago I gained 70lb over a year. I can't seem to lose it I'm over 230lb but I hold my weight very well so I look about 180. I am built and very muscley. I walk about 50 miles a week I do sports all year. my eating habits could be better but they are not terrible. in the pass year I've got down to 225 but it didn't say down. I'm 15 yo and 5'9. in just trying to lose like 30ish lbs but I cant. I don't know what eles I can do. any suggestions?