Doorbell won't connect to extender

I've tried two extenders with the same result.  Even located very close (like 2 feet) to the extender, the Ring goes thru its search and fails.  Other devices connect to the Internet (at high speed) via that same extender just fine.  I've confirmed that it is 2.4Ghz, not 5.  Nothing in the Help seems to apply here.  Any ideas?