Invalid value sn_ssr register

Hi, I have a question about a TCP connection between two WIZNET W5300 chips.
When I force a connection close during a send operation, the sn_ssr(x) register returns the value 0x10 or 0x11 on the next reconnection.

This value is not present in the W5300 datasheet (sn_ssr register table).

Can you help me?

Do you forcefully close connection performing DISCON command first, and then CLOSE connection and reopen socket from the very beginning next time (with OPEN) command?