I don't know if it's a right place, problem can be caused by GitHub cache API. my Github workflow sometimes in Haskell doesn't use cache key. not even more general restore keys.

as you can see there are multiple builds with same kay.

where pipeline each time could not find the cache and saves it again.

in my case i already have 5 duplicate caches with same key, which evoke my curiosity.
how it is possible? and what can be a reason?