I have five units, three x20 and two m4r. One m4r is connected through mesh, all the rest decos are backhauled. Firmwares are up to date. Most of the decos are showing offline in application and I am also losing a list of online devices. I have tried all the instructions provided here: https://www.tp-link.com/us/support/faq/1898/ but nothing is helpimg. I switched off the iPhone and iPad without a result. All decos are online and working, but I am losing information as described above. I used to have this problem earlier with older m4r units, but they were changed. Three weeks ago the problem appeared again and now I am having this issue almost all the time. The only deco that seems to be showing online is the main deco, the rest are offline, but actually they are not. Annoying.