@josve What is the firmware version of your Deco M9 plus? Is it 1.2.10 or 1.2.11? Please ensure that it is up to date. https://www.tp-link.com/support/download/deco-m9-plus/#Firmware If it is 1.2.10,...

@realjax Thanks for your reply. We are working on it and trying to figure it out. Any updates, we will let you know immediately. Good day.

@e3henri Thanks for your requesting. The 1.2.11 is the latest firmware for the Deco M9 plus; the reason why you cannot get the update is that the 1.2.11 is the original firmware of the new batch Deco...

@DroMike It can be that the end users just want to swap the location of the main Deco and slave Deco; or the current network diagram may have some problem, like unstability or slow speed; changing...

@Jnq Sorry for the trouble caused, we will do some troubleshooting first and try to fix it. 1. What is the current network diagram? 2. What is the led status of the Deco P7 when you lost connection?...

@david_h Hello David, thanks for your reply. Please try to change the DNS server of the main router to give it a go. Set the primary DNS server to 8.8.8.8, secondary DNS as 8.8.4.4. After that, try...