[1.7.10] Error in forge communication with bukkit

[MidacoYT]

i have a problem when i want to communicate my mod with my plugin(1.7.10 I know it’s an old version but I prefer it). I use an item to do this. When the player right clicks with this item he sends a packet thanks to sendPacketToServer, I added a debogging message to know if the packet was sent correctly and yes but only solo, if I go to my local server it is not sent.

There are no errors in the console.

these are my classes:

PacketPipeline: https://code.alwyn974.re/iyexowubux.java

PacketSendMessage: https://code.alwyn974.re/evihukoqoh.java

CommandExample: https://code.alwyn974.re/iliyidofop.java

ExampleMod(Main class): https://code.alwyn974.re/norayuzoha.java

Thx for help.