how do i remove deregistered hosts still showing up under 'Hosts' tab?

AX4-5F, FLARE 707.  No server Agents used so all hosts are added manually to the Storage Groups.

I added some clustered hosts to a Storage Group and got their IPs wrong, so I de-registered them and also destroyed the Storage Group.

However, they still show up in Navisphere under the 'Hosts' tab and what's even stranger is they are not consistent; e.g. host1 shows up 6 times, host2 4 time and host3 2 times. Zoning is such that each hosts has a path to SPA0,SPA1 and SPB0 SPB1, so in theory I should see 4 paths from each host, indeed that is exactly what i saw when i added them the first time.

The strange stuff started to happen after de-registering them.

The hosts are still connected to the AX4 but now under 'Connectivity Status' they do not all show up.

Is there a way of getting out of this mess I got myself into and starting again ? without rebooting the AX4 because other hosts are connected and working on it.

Does anyone think that a reboot of the 3 hosts would do it?

thanks.