can't receive expected response message for expected sampler

[yxt105926]

Sometimes I can't receive expected response message on time when i use websocket sampler. For example, when I send message {seq: 123456 , topic: XXXX} with sampler1 , I got some other response messages from sever. Then I trigger sampler2 , I got the {seq:123456 , response:XXX} in the first line which supposed to be displayed in the sampler1. In this case, I always get an assertion error for sampler1. I was using the Streaming connection , and also filled something in the Response pattern, but it doesn't work. Increasing the backlog doesn't solve my issue either. What can i do.....