the same function does not work the same.(recv_match)

[FreshJude]

1. the received.py

from pymavlink import mavutil
from pymavlink.dialects.v20 import common as mavlink2

receive = mavutil.mavlink_connection('udpin:127.0.0.1:14551', dialect='common')
while True:
msg = recevie.recv_match(blocking = False)
if msg is not None:
if msg.get_type() == 'VIDEO_STREAM_INFORMATION':
if isinstance(msg.uri, str):
print(msg.uri)
print(msg)
publisher.put(msg.uri.encode('utf-8'))
match = re.match(r"udp://([^:]+):(\d+)", msg.uri)
if match:
UDP_IP = match.group(1)
UDP_PORT = match.group(2)
print(f"开始接收视频流，目标地址: {UDP_IP}:{UDP_PORT}")

2. the send.py

from pymavlink import mavutil
from pymavlink.dialects.v20 import common as mavlink2

master_out = mavutil.mavlink_connection('udpout:127.0.0.1:14551', dialect= 'common')
video_stream_info_msg = mavlink2.MAVLink_video_stream_information_message(
stream_id=0,
count = 1,
type = 0,
flags = 0,
framerate = 30.0,
resolution_h = 1080,
resolution_v = 1920,
bitrate = 1000000,
rotation = 0,
hfov = 60,
name=b"test_stream\x00".ljust(32, b'\x00'),
uri=b'udp://127.0.0.1:5600\x00'.ljust(1600, b'\x00'),
)
while True:
master_out.mav.send(video_stream_info_msg)

These two functions work well with each other. But when I shut down the received.py, and change the port of send.py to "udpout:127.0.0.1:14550", which is another program's port. It does not work anymore.

3. another program

from pymavlink.dialects.v20 import common as mavlink2
from pymavlink import mavutil

self.rover_in = mavutil.mavlink_connection("udpin:127.0.0.1:14550", dialect = 'common', mavlink20=True)
while True:
msg = self.rover_in.recv_match(blocking = False)
print(msg)

Here is the output of " print(msg)" : UNKNOWN_269 {data:['fd', '49', '0', '0', 'a9', 'ff', '0', 'd', '1', '0', '0', '0', 'f0', '41', '40', '42', 'f', '0', '0', '0', '38', '4', '80', '7', '0', '0', '3c', '0', '0', '1', '0', '74', '65', '73', '74', '5f', '73', '74', '72', '65', '61', '6d', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '75', '64', '70', '3a', '2f', '2f', '31', '32', '37', '2e', '30', '2e', '30', '2e', '31', '3a', '35', '36', '30', '30', '14', '5e']}

I see that the message VIDEO_STREAM_INFORMATION number is 269, and it could be the reason of the error, but I can not fix it and I do not know why the almost same function work so well and I do not know how to change to MAVLink version2.