Sending TCP packet : ACK from peer problem?

Found at the W5500 data sheet:

At the TCP packet retransmission timeout, W5500 transmits TCP packets (SYN, FIN, RST, DATA packets) and waits for the acknowledgement (ACK) during the configured RTR time and RCR. If there is no ACK from the peer, a temporary timeout occurs and he TCP packet is retransmitted. The retransmission is repeated as many as ‘RCR+1’. Even after TCP retransmission is repeated as ‘RCR+1’ and there is no response to the TCP retransmission, the final timeout is occurred and Sn_IR(TIMEOUT) becomes ‘1’.

Is ACK problem can cause that a POST, sent to a server, is shown several times along with “tons” of extra meaningless bytes?
That is my current problem: No control of what is sent to my sever. Each transmission (same data) received differently…!

Any body has an idea?

Well, case is closed…Every thing work fine now. Changed to the last version of iolibrary made it.