Any persistent gas smell near a range is a safety issue, not a repair convenience question. Before anything else, avoid creating an ignition source — no light switches, no appliances, no open flame. Shut the gas supply valve off if you can reach it without difficulty, open windows to ventilate the room, and get everyone out of the house if the odor is strong. Make the call from outside, either to us or to your gas utility’s emergency line, and leave the inspection itself to a technician.
Finding the actual source is a job for leak-detection equipment once the area is safe: usually a fitting that has worked loose, a valve that no longer seats properly, or a problem somewhere in the supply line. None of that can be pinned down by smell.