how do i break up with my prom date

i (18f) have prom this saturday. one of my guy friends set me up with his friend (who i've never met irl) for a prom date and he said yes BUT I DON'T WANT TO GO WITH HIM!!! i only agreed at first because he offered to pay for his own ticket so i was like why not. we've been texting and hung out once but i was not feeling it. he is also still texting me. i also have another guy that agreed to go with me and he is slightly more pleasing to the eye, but his stupid ahh responded too late. what do i do i hate ts. 🥀🥀🥀