ERROR: Message too long

[Krit007]

I use ESP8266 non-os make communication between ESP and gateway by mqtt protocol. How to solve this problem. Help me please!!
TCP: Connect to ip 172.16.6.119:8883
please start sntp first !
client handshake start.
client handshake ok!
MQTT: Connected to broker 172.16.6.119:8883
MQTT: Sending, type: 1, id: 0000
TCP: Sent
TCP: data received 0 bytes
ERROR: Message too long
TCP: data received 4 bytes
MQTT: Connected to 172.16.6.119:8883
MQTT: queue subscribe, topic"esp/test", id: 1
MQTT: queuing publish, length: 39, queue size(17/512)
MQTT: Sending, type: 8, id: 0000
TCP: Sent
TCP: data received 0 bytes
ERROR: Message too long
TCP: data received 5 bytes
MQTT: Sending, type: 3, id: 5465
TCP: Sent
publish success!!