There is a mode where the recirc button flashes to tell you it
will only be used for a few minutes (then it gos back to vent from
the outside). I see this if I press recirculate and hold it down
for a couple of seconds. If I press quickly I don't see the flash.
Manual has details (not the best user interface, thats for sure).

But, flashing lights also are used to indicate a system problem.
Are you getting cold air. In other words is it working except
for the flashing light? If it is not working, a dealer needs
to pull the error codes from the system as the first start in
determining what is wrong.