If you want the full version and license for commercial use,
you can purchase here :

https://fontkong.com/product/sunnday/

File Font Version : 

1. Sunnday.otf
2. Sunnday.ttf
3. Sunnday.woff
4. Sunnday Italic.otf
5. Sunnday Italic.ttf
6. Sunnday Italic.woff