I use a great car rental service at LAX. I've tried to put a glowing review on their Yelp page to help them get business to no available. It doesn't even show u

I use a great car rental service at LAX. I've tried to put a glowing review on their Yelp page to help them get business to no available. It doesn't even show up. I'm guessing this is because they choose not to advertise with yelp either? I just wrote another review right now to test this out again, and my account shows I have written two with them. Why is Yelp not displaying these on their business page, and their star rating is unchanged?