New to the forum guys, cut me some slack.

Having problems with the mud buddy 37 efi. Took it out fishing the other night, ran for about 30 minutes, turned it off. About a hour later I tried to crank it up and it turnes over just wouldn't crank. Thought I might've got water or junk in my gas so I took it home and drained it and put new gas and spark plugs in it and still wouldn't crank. Came out the next morning and it fired right up. Ran it for about a hour in the yard turned it off and it wouldn't crank back up??? Any help would be nice.