Item sets disabled?

I cant tell for sure if this is for everyone because I cant find any recent news on item sets but there seems to be no way to enable item sets, i tried a few times going through all options, trying to enable on all champions changing maps back and forth but no matter what I did the item sets did no appear in game as a gangplank main the recommended items are way off from what you should build and I would like to know if there was any way to fix this?

Thank you