Internal Exception: io.netty.handler.codec.DecoderException: java.lang.IndexOutOfBoundsException: Index 25 out of bounds for lenght 5

I have an old minecraft server where i used only PaperMC , then i changed it to Arclight to have mods and plugins.

When i opened up the server starts normally but when i put the ip and the other ip with extra numbers it say "Can't connect to server" so i tried to enter anyway and appears.

"Internal Exception: io.netty.handler.codec.DecoderException: java.lang.IndexOutOfBoundsException: Index 25 out of bounds for lenght 5"

btw i use official Minecraft launcher and my nickname is short.

Also aternos doesnt notify me anymore when i changed to arclight

Log with opened server:

Quote from Roman

Did you already install mods? Or is it still running with plugins only?

Yes I installed 3 mods and the opened it, the first time take a long time to load and then when it's was loading it closed

ok so anyway i deleted all mods and i realized it was create that needs flywheel but it doesnt come yet to 1.19