How do I not lose interest in my favorite things?

I(M19) have been lately observing a trend in my life that all the things that I cherished become boring for me out of nowhere. The strangest thing is that it’s not going gradually. It’s just one day when I try to do something, or consume a media that I liked a lot and it just fills very mid for me for some reason.

For example I used to be a really big Harry Potter fan. And I’m talking like stereotypical Potterhead. I’ve listened to all of the audiobooks at least a dozen of times(it’s easier for me to focus on audiobooks rather than regular books) and every re-listening gave me as much joy as the previous ones. But one day I tried to re-listen the 7th part when I realized I cannot go past first chapter without losing interest.

The other thing is music. I used to love a lot of artists, but now their music does not hit the way it used to, and I can’t seem to find other artists who made me feel that way. I also loved windsurfing but for last two seasons I can’t find a courage to go back to it, even though I live literally 1km from the spot I I’ve been always going to. I’ve recently rewatched Tron Legacy, which I loved with all my heart since I was a kid, but this time it didn’t feel like I’ve been watching a favorite movie, more like a PowerPoint presentation describing the plot.

Right now I’m scared to try anything I liked in the past in fear that it won’t give me as much joy as it used to. And about trying new things I can’t keep my mind to them for long. It’s like a quick fazes, I lose the interests them quickly.

I know it may seem like a very normal thing, but I feel like those things that I lose interest to are a big part of me and losing them feels like losing part of me in some way. I would really appreciate any tips on how to get rid of this feeling or how to not lose interest in my favorite things