Getting sudden “blocked” errors

Hi!

At one of our clients’ site there’s a suburb recycling locations map, powered by your plugin.

Recently it has begun throwing “403r Access Blocked – Referer is required by tile usage policy of OpenStreetMap’s volunteer-run servers” error tiles every now and then. They may or may not appear and disappear by zooming in and out the map.

Absolutely no idea where the referer should be added, how to add it and what it should be consisted of. Couldn’t find anything related to this at the LeafletMap plugins settings.

Any ideas, how to fix this?

The page I need help with: [log in to see the link]