@chromenumero If you have active cable TV then you should have a MoCa POE filter to prevent signal leaking to the outside, it should be placed at the highest splitter point of the network hierachy (normally it's at the demarcation point when cables enter your house). But since you have fiber internet, it's not necessarily needed, you can just unplug the incoming feed cable at the demarc point instead. I have CenturyLink fiber with a MoCa for my garage and I did that. I don't really think that is the cause of your issue though. I do feel like there is an unstability at one of your Deco units. You did mention that previously without the MoCa your network works just fine, then I would double check the MoCa setup, check for loose connection or loose outlet somewhere in the line.

Whenever I accidentally unplug one of my Deco satellite units (I've been installing switches in my house so sometimes I have to trip down the circuit in that room). I notice that the network will suffer from unstability for the next few days until I reboot the whole system. From my observation through those couple times, it looks like broadcasting packets were suddenly dropped when one of the units went down, then when the unit got connected back those broadcasting packets be like, oh you're here and they flood the whole system again, which cause the dropped connection or unstability of the whole network. That's why I have to manually reboot system after one unit dropped. They would work normally again, but in your case I suspect that the unit with MoCa adapter going down a lot for your system to have to dropped connection every day like that. I would make sure to check that MoCa setup, maybe swap out 2 MoCa positions, or swap out to another MoCa set, check the coax cable as well.

Here is my setup:

                                                     > 2nd Deco (Ethernet)

ONT > Main Deco > Main switch > 3rd Deco (Ethernet)

                                                     > 1st MoCa adapter > Coax outlet in my garage > 2nd MoCa > PoE injector > 4th Deco X50 Outdoor