SkySafari 6Pro connection problem

I connect my EQ-6R Pro via RS232-Serial-cable als SkyWatcher Mount (ASCOM) to my Laptop. Mount control works flawlessly. I start WiFiScope and it connects successfully to “SkyWatcher Telescope”.
I note IP- and port-number, then in SkySafari Pro 6 I select “SkyWatcher SynScan” as telescope type
and enter IP- and port-number. When trying to connect, I get error message that SkySafari can make a
wireless connection to the scope but the scope is not responding.
Any help or idea how to fix this would be highly appreciated!

Thanks, Helmut