Yeah, my experience was always pretty bad as well! We talked a little about it here: Podcast: Music PR Made Simple: DIY Strategies for Independent Artists - #3 by Mel
I haven’t found anything better than a spreadsheet to list relevant curators, and to track submission dates and any responses. Then emails or DMs (if they prefer that). Now I’m off Insta, DMs are not an option anymore, soooo… lol!