I have 2003 hyundai sonata went to get a inspection but can't read OBD raeding help!?

the station inspector tried to read OBD reading can't read it shows not ready... no responds and The Inspector told me to go to the dealer to reset the computer. I went to dealer and they told me to drive around for a week and try again. if that doesn't work dealer will take a look at the vehicle. any ideas cheapest way to fix.