Hi Egemen,
I have the same thing happenning on my SG300-10P, see screen capture below.
Then I plugged some devices into ports G8 and G9.
It was noted that the status changed to the following, see screen capture below.
Check your link state on the front of the switch or use to GUI to look at the port states. If one of those two ports does not have link, the switch will report "not ready."
You may find additional useful information under status and statistics> view log >ram memory can give you details about what is happening with port states, so check your error log.
( note: logging may have to be enabled via Administration >log settings )
regards dave
