Isochrone returns points with 3 coordinates

Hey, guys. I’m running GH on a server from a copy of north-america-latest.osm.pbf obtained from geofabrik.de. I like it a lot, but I do have a small problem. Unlike when I tested my code on your API, every isochrone request from the GH server I’m running returns geoJSONs with three coordinates per point, like so:

[-85.77933610296256, 38.26650564409432, 0.5]

I’m currently filtering these out in post-processing, but if there’s something I missed in the query or the configuration I’d love to know so I can fix it in a better place.