slo:GeoLocation is missing

i'm just trying to retrieve via sparql interface the indexed geolocation data with the following command:

tracker sparql -q "SELECT ?u WHERE { ?u a slo:GeoLocation }"

it returns 0 such record but when I examine files with tracker info any_image_with_gps_data it does have a record slo:location that refers to a resource with an uuid.

if i use the tracker-extract binary and use json-ld output it does provide me a node with the right data in it (gps location).

i'm using debian buster version of tracker, i.e. 2.1.6

one more thing: the sqlite3 database's "slo:GeoLocation" table has 0 rows.