Netgear Portforwarding Problem after using the IOS app

After login via the IOS app into the router and set some settings the app, the port forwarding list is empty (this is reproduce each time). Also when the missing forwards port are added after this inlo the "empty like list" an error will be occure, because the port forwarding exist. Because the list is empty, the existing forwards coudn't delete. The forwarding are working till the router is restarted, the list will be stay empty and couldn't restore anymore. Also the problem with the restoring a good configuration file, I didn't got the table again. Solution is to make a hard factory setting reset via the reset button on the router and set all values in the configuration again.