lwgy

Hi so i am making a script where all players see a GUI at the same time with some books and stuff and then a random challenge is picked, well this works great in singleplayer but when there is more people on the server it shows it to one person first and after its completed goes onto second one..... so this is a problem because it takes about a minute for it to complete so when there is more people online this would take a long time to finish. i would send my code here but its about 200 lines of code so im more looking for a general solution why this happens and then ill implement it in my code, thanks!