Fuel prices decrease

I have being to a caltax fuel station were I have full up fuel on the 3rd of July and when I asked why isn't the fuel price changed the management says the fuel price will be charged from the 4th which I didn't think it's was the truth so I then called the caltax customer service and spoke to and agent and explained my issue and the she told me to hold on the line she then comes back on the line and tell me that her management says that only caltax will be changing they prices on the 4th of July which is really a big joke because when fuel prices goes up they don't keep it the same price until one day later at 12 midnight the price is change or they tell you they out of fuel this is really sad for people like me who's always on the road !!!