If you have suddenly lost your OSM feed, a recent change made by OSM may be the cause of the problem.
This may well solve the problem.
Go back into OSM to where you generated the keys.
Click 'Edit' on the box and then within the pop-up tick 'Client Credentials Grant' and then click Save.
Go to your website, click on OSM in the sidebar, re-enter the keys and, fingers crossed, it should work.
Remember to tick the Waiting List and/or Events box, depending on what you use OSM for.
