No answer above is satisfactory.
I have answered this question in "All our X" vs. "all of our X", but let me rephrase here.
Listen to all of your fans
Listen to all your fans
"All of your fans" and "all your fans" are both correct. They are different in that in the first sentence, "all" is a pronoun, while in the second, "all" is a predeterminer that comes before the determiner "your", helping to further specify the noun "fans".
You may wonder the difference in the usage. A linguist explained, "[...]the variant without “of” is significantly more common than the variant with “of”, to such a degree that the variant with “of” might be considered unnatural (or colloquial) by some native speakers in certain contexts. My advice is: If in doubt, do not use “of” between “all” and another determiner." (https://jakubmarian.com/is-it-all-the-or-all-of-the-in-english/)
He explains better than Michael Swan.