UDP packet invalid protocol version (Chirpstack v4)

Hello, I try to simulate a UDP gateway packet forwarder to the Gateway Bridge but the server could not handle packet, this is the server error:

level=error msg=“backend/semtechudp: could not handle packet” addr=“10.244.4.59:41732” data_base64=MDIgMTAgMTAgMDAgMDAgODAgMDAgMDAgMDAgMDEgQTkgNDMgN0IyMjcyNzg3MDZCMjIzQTVCN0IyMjc0Njk2RDY1MjIzQTIyMzIzMDMyMzMyRDMxMzAyRDMxMzI1NDMxMzYzQTMyMzEzQTMxMzcyRTM1MzMzMjMwMzMzODVBMjI3RDVEN0QK error=“gateway: invalid protocol version”

This is the UDP packet from an UDP client :
02 10 10 00 00 80 00 00 00 01 A9 XX 7B227278706B223A5B7B2274696D65223A22323032332D31302D31325431363A32313A31372E3533323033385A227D5D7D

const protocol = “02”;
const token = “10 10”;
const pushdata = “00”;
const gateway = “00 80 00 00 00 01 A9 XX”;
const payload = “{"rxpk":[{"time":"2023-10-12T16:21:17.532038Z"}]}”;

What the mistake ?
Thank you