Hawtio - ActiveMQ Issue

Could someone help me with the below issue?

1. I gave credentials in preferences for ActiveMQ.
2. I created Queue in the default broker and it was successful.
3. I selected the queue and clicked on the Send button in the top menu. The
message was sent successful and I was able to even see my message when I
clicked on Browse.
4. But weird stuff is, I clicked on the Operations menu and selected the
'Send text message(java.lang.string)' and gave the body as 'Hi' and clicked
on Execute. But unfortunately, I got javax.jms.JMSSecurityException: User
name [null] or password is invalid. For topic also, when I select send
menu, message was sent successful. But getting same JMS exception when
trying to send message through Operations menu.

-Thanks