Error code C4A1/C192A18 no controller error

Hello, when we were testing UR5, when we pressed guard stop, TCP kept sending mobile packets. After 1 minute of testing, the robot arm will report no controller error, displaying error code C4A1/C192A18. The phenomenon is steadily reoccurring, and we don’t know what the problem is. Have you met any other manufacturers? Help analyze it. TCP port number: 30002