The APP shows an alert "Base connection not possible: Other client already connected". What's going on?

Nothing serious. In some collision cases (e.g. WLAN connection is lost during the transfer) it may happen that the base station did not discover that the APP is no longer connected. In this case, do not try to connect to the base for approx. 10 minutes. After this timeout the base will reset the broken connection and the APP can be connected again.

Possible collision cases
   - WLAN connection is lost <s>
   - WEB-configurator is still in use of Gigaset IP device