Days until next birthday (Countdown)

Hi dear community, 
I got everything in this Excel-File as I want it to, except the countdown until the next birthday and it really pi$$es me off! 😡 It's probably a formatting (number, date etc.) error. Would be awesome if anyone could help - for real!
https://docs.google.com/spreadsheets/d/1EUFu23AkVBWZH6Wz6RXiRpxZkigWdJzF/edit?usp=sharing&ouid=112729717884996737177&rtpof=true&sd=true
Happy New Year's Eve to y'all and all the best for 2025 for you and your loved ones!
Sandro
🎉🥳🌟⭐🤩✨