Number appearing by Icon

[68bucks]

I downloaded the app for this website and it works great but I have a number that appears by the app icon. It looks like a new message notification> originally I went into the app and saw there was a new message, welcome to the forum or something. I read it and the number was still there. I deleted it and it went away. Now the number has reappeared and there are no messages at all. I rebooted the phone and it is still there. Any ideas?