Postgres logs: Error messages every 60 seconds

The following error message appear every 60 seconds on my instance's postgres logs:

2019-01-22 01:47:15.049 UTC [11524] ERROR:  relation "users" does not exist at character 58
2019-01-22 01:47:15.049 UTC [11524] QUERY:  SELECT COALESCE(users.follower_address, '')         from users where users.ap_id = actor
2019-01-22 01:47:15.049 UTC [11524] CONTEXT:  PL/pgSQL function public.activity_visibility(character varying,character varying[],jsonb) line 6 at SQL statement
        automatic analyze of table "pleroma.public.activities"

...

2019-01-22 01:48:14.994 UTC [11526] ERROR:  relation "users" does not exist at character 58
2019-01-22 01:48:14.994 UTC [11526] QUERY:  SELECT COALESCE(users.follower_address, '')         from users where users.ap_id = actor
2019-01-22 01:48:14.994 UTC [11526] CONTEXT:  PL/pgSQL function public.activity_visibility(character varying,character varying[],jsonb) line 6 at SQL statement
        automatic analyze of table "pleroma.public.activities"

Thanks for looking into it. Cheers!