Reneil Juco

So I'm in need of a smog check. No Check engine light, and car runs fine. When the smog check shop plugged into the obd2, it read not ready. I plugged my bluetooth obd2 reader and it reads the catalyst as incomplete. The person told me to drive around for a couple days on and off the freeway. I've now driven 300 miles but still reads the same. What do you all think I need to do. Thanks in advance!!!!!