As I experienced the same problem on many websites I manage, I found that deactivate then reactivate ACF Pro licence allows me to restore the update feature for concerned projects (mailnly OVH servers and localy hosted websites).
I often start a new project from a clone of a preconfigured WP install (files, plugins and parameters) containing ACF Pro already activated, so deactivate/reactivate solved this in my case.
Hope it helps!
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