Question: What defines maintenances_last_missing flag?

So im doing some tests in SecurityServices and in the API there is a flag: [‘data’][i][‘SecurityService’][‘maintenances_last_missing’]. What exactly is changing it? I have one SS where I added a maintenances for todays date but it’s saying that its all “ok” and the the [‘maintenances_last_missing’] is still 0 even when it should be 1. In the web as well it should say “Last maintenance missing”.
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