This was actually one of only two pieces that I played on my recorder. Beautiful theme.

I'm more of a fan of banger OSTs than the relaxing ones but:

Can't go wrong with Dearly Beloved.

This is also dope too. Even better than the original.

Skyrim background music. Most of it.

Blue Destination from Trails of Cold Steel II.

Dire Dire Docks is a great choice. There's more great choices here. I'll put in two more, and to keep up with my reputation they're two Zelda ones;

Majora's Mask; Clock Tower/Song of Healing

The Wind Waker; Grandma's Theme

You can say what you want about The Wind Waker, and I do myself, but the music was on point. Koji Kondo himself once did a beautiful piano version at one of the series 25th Anniversary concerts.

genshin impact has many relaxing world map music. Slumbering lore is probably my favourite

The original safe room music in Resident Evil is pretty goddang relaxing. I guess the effect is heightened if you're actually playing and find reprieve in those rooms.

Some others that come to mind: