Feeds showing update interval of none

I just recently started having a strange issue where a few feeds show update interval “None” on the feeds list. However, when I edit the feed it is showing the correct interval, it happens for different intervals as well not just one type. Furthermore other feeds with the same interval are appearing correctly on the list. I just recently started getting this issue, after I created around 200 feeds. This concerns me because I am planning to create many times more feeds. Anyone else encounter this problem?

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