Hi Zeeshan,
I believe the answer to your issue lies within the attached diagram found here Authenticated web messaging (genesys.cloud).
While I have not personally setup authenticated web messaging, I think I have a good general understanding of why this is happening. In the below image, after the customer authenticates note step 10 "Open web messaging". To me this means the Web Messaging service does not launch or appear until you are an authenticated user.
From a design perspective this makes sense, otherwise unauthenticated users could just interact with your web messenger window. You specified that you enabled authentication, but did you authenticate in your testing? If not, I would authenticate yourself first.
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Caleb Smith
Interstate Gas Supply, Inc.
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