Problem between ReadyNAS ultra 2 and Netgear D6300 router

Hello everybody!

It is the first time I write on the forum but I read several times your discussion to fix problem in the past.

This time I did not find anything helpful and I decided to ask you directly.

I have a Ready NAS ultra 2 and a router D6300 in my house. Everythings worked fine in the last year since suddenly, last week the router started to not find anymore the NAS. Btw it continues to proper recognize my other NAS a Duo v2.

I tried to change the ethernet cable, to change the port on the router, to change the connection by the ethernet plug in 2 on the NAS but nothing. I re-installed the OS 2 times but without results. 

After that I decided to plug the NAS directly on my laptop and magically it riappered. The storage in X-RAID 2 are ok and the registry does not show any issue. If I try to configure the NAS with the ethernet port 2 on the house network it doesn't work.

In my opinion is a problem between the router and the NAS but I don't any additional Idea on how to fix it.

P.S: Raidar version 6.0 find the NAS when is directly plugged in on the laptop but obviously not when the NAS in connected to the house's network. On the contrary everything is ok with the other NAS..

Please help me.

Thank you