You should update to 4.1.2.1 if you really have only 4.1.2.
See Foreman 2.4 / Katello 4 unable to sync repos and https://pulp.plan.io/issues/8133
As far as I understand it is being backported to pulpcore 3.14 in https://pulp.plan.io/issues/9130 so I guess it should come up in Katello soon.