RabbitMQ bad_header

I am new to RabbitMQ. I have setup RabbitMQ server in my local machine and trying to test it out by publishing a message to a queue. But connection (from postman)
fails

and I could see below entry in log file.

2022-12-03 10:19:28.722000-07:00 [info] <0.702.0> accepting AMQP connection <0.702.0> ([::1]:64594 -> [::1]:5672)
2022-12-03 10:19:30.808000-07:00 [error] <0.702.0> closing AMQP connection <0.702.0> ([::1]:64594 -> [::1]:5672):
2022-12-03 10:19:30.808000-07:00 [error] <0.702.0> {bad_header,<<“123\r\n\r\ns”>>}

I tried to test connection with telnet, but even then I see same error in log file.

Can somebody guide me to where I am going wrong here.