Hi Prashant,
could you please share the microflow you built with us and the errormessage in the console/application log?
If there is no error in the console/application log, it might be caused by triggering the microflow “ synchronously”. In this case an error will be visible in your browser log. Very boldly it means the functionality takes too long to finish and loses connection between client and server, causing an error only on the client side.