Blocking is not reflecting on backstage

When blocking a publisher from the Backstage platform, the change is immediately reflected in the campaign publisher_targeting object via the API.
But when updating this object (publisher_targeting) via the API, the change is not reflected in the Backstage platform - even after a page refresh.

This is the call we make to block publishers:
patch: https://backstage.taboola.com/backstage/api/1.0/[redacted]/campaigns/5602922
Payload: {"patch_operation": "ADD", "publisher_targeting": {"publishers": ["lemaleadmachine-tipsandtricks"]}}

Could that be a UI cache on the Backstage platform? Or are we missing something?