@oij20 Hi, welcome to our community. You may try to reset the Deco M4 and reconfigure them one by one. How to reset: use a pin to press the reset hole for one second, then the Led will go flashing...

@Andrasd Hi, thanks for posting question here. That should not affect the wireless coverage. This guide is for your reference: What’s the difference between Access Point mode and Router mode on the...

@Vlassis_ Hi, welcome to our community. I am afraid that we have no such a recommended list of 5G antennas. For the antenna installation, this introduction in the thread is for your reference.

@SebaFene Hi, thanks for your detailed update. To assist you efficiently, I've forwarded your case to the TP-Link support engineers who will contact you with your registered email address later....

@Steve00 Hi, you may set bandwidth control with Download 1000 Mbps/ Upload 1000 Mbps, without devices prioritity. Then that will not infuence the overall performance.

@Yeong Hi, thanks for posting question here. You may update firmware to latest 1.2.8 according to the official website. How to Update the Firmware of Deco