Gas range has the wrong burner try to ignite
In my experience, most spark ignition ranges spark all the burners at the same time.

So, it's probably just an issue with that burner not sparking - spark gap shorted out with food is the usual cause. Broken wire is possible but much less likely.

Try looking at the left front burner spark (which you see when trying to light the front right) while lighting each of the back burners. I'll bet it sparks for both of them, too; and I'll also bet the back burners will spark while you are lighting the front ones - you probably just haven't looked for that before.