Orbi RBS750 showing empty status page

I got a network with RBS750 router and 3 RBS750 satellites.

After a power outage 2 of the satellites did not have stable wifi anymore. Logging in to the status page of the satellites did not work at all. After resetting the RBS750s both of them were able to resync but when I try to access the status page I get a blank screen. For the 3rd satellite a did a reset and resync as well and it show the status page correctly. Firmware version is 7.2.6.31. Since that power outtage my WLAN is somewhat unstable, I experience a lot of reconnestions. I already found the hint to downgrade to 7.2.6.21. 

But at the moment I have no idea how to get those 2 satellites to be accessible again. Without that status page there is no chance to do a firmware downgrade.