Why does my 2019 Kia Sportage show the parking light symbol on the instrument cluster instead of the headlight symbol?

It doesn’t sound right, does it. And why would Kia even include a low-beam light indicator if it wasn’t to show that the low-beam lights were, in fact, on?

You should be able to figure it out by looking at the owner’s manual for your car. I managed to find such a thing online for your model Sportage, and it shows only a high-beam indicator light and a lights-on warning which covers both parking lights and low-beam. That suggests that your dealer is correct.

The other question, however, is what you’re looking at that makes you think it’s a low-beam warning light. The answer could be that there are two high-beam indicator lights, one for the manual high-beam operation and another for the automatic high-beam if your vehicle has that fitted. Perhaps it’s the fog-light indicator you’re seeing. Again, your owner’s manual should spell it out for you.