Internal Exveption: io.netty.handler.codec.DecoderException: The recived string length is longer than maximum allowed (20 > 16)

I am using prefixes with the scoreboard system. I am using them on my minecraft server which is running 1.8.9 of Minecraft server. This occurred right after i changed the prefix and when I restarted my server. I see other servers that have it working and I just want to look as cool as those vanilla servers.

Thank you,
Have a nice day sorry for my bad grammer.