Hi @balajeek, welcome to the Caddy community!
I edited your comment to put your Caddyfile in code blocks (triple backticks, ```) for readability. Putting URLs in code blocks doesn’t count towards link spam, too.
Your Caddyfile configuration looks good. This is a universal problem, not any mistake on your part. I’ve had plenty of opportunities over time to write about this issue on these forums, actually. Here’s a recent one that explains the problem as another poster encountered it:
Have a read of that post - the rest the thread also has some useful information - and post back if you’ve got any questions.