Permalinks of posts sometimes show subcategories, sometimes they don’t

Hello everyone,

On my post page, I have some post permalinks that are correctly set up, as intended, with the following structure : /blog/category/subcategory/post-name

However, some of my posts, for an unknown reason, have their URL without the subcategory part while breadcrumbs remain correct in any case.

The only thing I can notice is that the disappearance of the subcategory part only occurs for my last few posts.

I really wonder what is going on, as I have already reset the permalink structure several times. Do you know what can cause this odd behaviour?

Thank you,

Léo

Ps: I have checked the forums to see if this topic already exists but I could not find anything resembling.

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