After the last update in can choose both 2.4 and 5 together 

Or only 2.4 or only 5

Some of the house members can only use 2.4 so you choose both 2.4 and 5

But now those who connected before on the separate 5 ssid are on the same both option and the speed is as fast (slow) as the 2.4.

Even that it say connection speed 8xx mb

Why ? Can that be solved

Thanks