Router not assigning IP addresses after power outage

My router does not  assign all IP addresses after power outage.  Some devices get an IP address, others do not. It appears to me that hardwired devices are typically fine, the problem seems to be mainly with Wi-Fi connected devices. I solve the problem by a hard restart (unplug) the router.  Sometimes this works on the first try, sometimes it takes two or three times before everything is back to normal. A soft restart of the router does not solve the problem.  I see some solutions here that say to do a factory reset of the router, but that means setting everything up again.  That seems like a very crude fix and hardly a solution to what appears to be a router firmware problem.