[Can't use server at all, can't even try to fix it]

I made a new server and tried to play it, but every time I try to join. it gives me a failed to connect error, and in the dashboard I can't start the server. I reset it but that didn't fix it, and force hibernation gives me an error to "contact an admin". What am I supposed to do?

[Do not give creative to people who ask for it if they say they want to make something "cool" cause they will add a sign or book with a link that will ban everyone from the server and make them op.]

So i was in my server, playing, and someone joined, and said "Hey, can i have creative? i want to show you a cool wand. If i do anything bad you can ban me" and i just decided to see what it was cause im stupid like that, he gave me a book, i clicked on the text, bam. he was server operator, banned everyone in the server, and probably planned to wreak havoc everywhere. DO NOT, AND I REPEAT, DO NOT DO WHAT I DO. ban these people as fast as you can.