I'm on a Linksys WRT1900ACS, latest version of OpenWrt (18.06.4 r7808-ef686b7292). I've been using my router for months now with zero issues, haven't even had to restart it, but this morning when I woke up I discovered that my wireless networks have no internet connection. I have two networks, 2.4 and 5GHz, neither can connect to anything (not even the router control panel). My wired connection is working just fine.
I don't know what I did earlier today, but after I restarted it a few times it started working. I had been on it all day, then about 30 minutes ago it dropped again.
I haven't changed anything at all in several months, so I'm not sure what's going on. Restarting the router didn't help and I'm at a loss for what else to check in my config.