Duplicate Data to http post api

My node sends data, and each frame is received by server, no signal FCNT miss.
But some time I get multiple data of same FCNT, I watched live frame, and doesn’t found any duplicate FCNT data there, and also checked log of node, it is also doesn’t sending duplicate FCNT frame.
I am receiving duplicate FCNT data( same data send by node), on http server.

I think may be issue from http post.
please guide me for this issue.

Thank You