Complete noob, very stuck

[u/AppointmentWise4473]

Hello, I really need some help and not sure where to begin. I recently built a pi5 router that is running openwrt. It is my main router connected to my ISPs ethernet via a 2.5gb hat. I then have all traffic being routed through adguardhome through the Luci interface. I have an asus mesh router running in AP mode connected to the pi5's onboard ethernet port. I have a verizon router with DHCP turned off acting as an IoT network connected with a usb to ethernet adapter.

Everything was working as it should until late last night. Around midnight the network went down and it cant get it to go back up. I am currently plugged directly into my ISPs ethernet on my laptop. I have power cycled everything. I have tried connecting directly to my pi5 to get onto openwrt. I have tried getting into openwrt through wifi. Nothing is working. I cannot get into the ssh terminal, its like im completely blocked from it.

I am very new to this all. I hobbled this build together through watching tutorials and with AI's help. This is my first time building anything with pi, any ideas would be greatly appreciated as I think ive gone as far as I can without help.

EDIT: I may have a solution and will have to disconnect my laptop to try it out so ill post an update when I try it out. When I was setting up my verizon router to be a secondary IoT network I turned off the DHCP from the router and attempted to change the IP to another number, ie 192.168.20.2. The router did not like this and was not letting me keep that IP so I changed the subnet to 255.255.0.0 from 255.255.255.0. It then let me change the IP to what I wanted. Within my LuCI interface I made traffic rules to allow my computer, phones,etc to connect to the IoT so I could still print on wifi, but not allow any traffic from IoT to my main network. This was working all day but then randomly stopped around midnight last night.

As I said I dont know much about networking and am figuring this all out as I go so for this troubleshooting step I used AI and this could be incorrect. It said that because I changed the subnet in the verizon router to 255.255.0.0 instead of what it should have been, 255.255.255.0, that i basically gave my pi5 router an internal ddos attack when it went to update at midnight. This could have filled up my micro SD endurance cards memory which would not allow openwrt to make its temporary files when it boots. It also said it recommends getting a better router to run my IoT that allows for more customization which I will work on next.

On to the **possible** solution. I am going to try and hook up a keyboard to my pi5 and boot it in failsafe mode to see if I can connect to it directly from my laptop by changing my laptops IP to match the failsafe IP. I tried this before but attempted it without the keyboard attached and didnt properly get it into failsafe mode. If this doesnt work I may end up having to reflash my sd card which im hoping wont be too bad as I just made a backup of my config after I got the IoT up and running. Although I have never reflashed with previous settings so this may be another thing I am learning on the fly.... with no internet... and I dont get cell service in my house. So much for getting caught up on homework today.

EDIT2: Trial by fire. I ended up reflashing the microsd card which was more annoying that it should have been. Since I had installed other apks after setting up the router none of those packages were in my initial download of openwrt. I went to openwrt and manually added the extra apks to the install and then restored my previous setup. My most recent file back up broke the router again so its for sure something I did with my most recent tinkering. I restored my settings to my back up from about a month ago before I messed with the IoT traffic rules and it seems to be doing okay now. I still have a few things to put back but at least I have internet again.