I found it, The remote platform use not allow a Null value.
Just change it allow and all is back to normal.

From: duduhandelman@hotmail.com
To: observium@observium.org
Subject: Map and Neighbours
Date: Mon, 23 Mar 2015 09:47:35 +0200

Hi All,
For some reason I don’t have the Neighbours and Map tabs under the ports page.
It's probably something that I have change but I'm unable to find it.
Also the mysql link table is empty.

Any idea?

Thanks
David