How do you get a 17 year old boy to like you?

im 15 years old and hes 17. we have been really good friends for about 3 years and we text most days which are normally quite flirty. we were seeing eachother about 7 months ago but finished two months later as we couldn't see each other as we are both competitive swimmers. But my feeling have never gone away and i think i love him. here is my problem, i need to get him interested again. we are still really good friends but i don't want to be stuck in the friends zone, i need him to feel those feeling he used to feel for me. does anyone have any ideas?