Hi Snehal,
Since the same code works in QA but fails only in Production, this is likely an environment-specific issue rather than a microflow issue.
From the screenshot, the request is failing with an HTTP 500 (Internal Server Error) before the microflow executes. Since even the first log activity isn't reached, I'd check the following:
Could you also share the runtime logs around the time of the button click? The browser console only shows that the request failed with a 500 error; the runtime logs will help identify the actual root cause.
Kindly mark this as the accepted answer if it helps.
Added one screenshot. But still the first log activity in MF is not logged