Why is there an orange flame instead of a blue flame from my gas range?

Usually this is due to having too rich a mixture. (That's too little air for the amount of fuel being burned.) On rare occasions, there's another cause. If you run a humidifier in your house, mineral particles in the air can cause the flame to turn orange.

A yellow flame is lack of oxygen, not orange! Unless this stove is ancient there is nothing to adjust and highly improbable that suddenly out of no place your air/fuel mixture changed. You can get orange just by blowing dust in the flame. Have you had anything spill over onto the burners that might be burning off?

There is a higher concentration of air running with your gas in the lines than there needs to be.

your air fuel (gas) mix is off this can be dangerous for some one to fix with out the knowledge please call a repairman asap this can also let or cause to much cordonmixide in your home

Lack of oxygen.....