Are there Notification limitations?

[chrsmrrtt]

Hello. I have a collaborative playlist that a friend and I contribute to on a daily basis (add a song you think the other will like once a day). During the early stages I would recieve notifications each day about his additions but I now don't recieve any. Is anyone aware of any frequency limitations applied to notifications?

 I still recieve notifications about other playlists, usually Spotify curated ones which are updated less frequently.