Only treasures are caught while fishing

I have been working on a server for a week now, but today I noticed something rather weird. This was the first time I tried fishing, and I only got treasures. I got name tag, lilypad, enchanted books, bows and rods. Only treasures basically.

Is there some option I can change to disable this?

I tried searching for others having similar problems, but I actually found zero other problems like this. Only fishing enhancement plugins appeared as search results.

If there is any additional information you need, please let me know.

Thanks in advance for any help.

 

It's been over a week with no replies. Am I really the only one experiencing this?
The only plugins I had installed as of the start of the problem was Essentials.
I've had to make a plugin that changes the caught item to a raw fish as a temporary fix. As silly as it might sound.

 

Plugin list Please.