Every glitch, bug or problems my apple watch has.

So I have had an Apple Watch SE for 2 years, and my Apple Care expired. I have many bugs or problems with my watch; here is a list.

1. My Activity app has a glitch where my Longest Move Streak badge is stuck on 35 days and the Move Goal 100 badge to (sometimes it will get to 34 or 36) (this has been happening scince I bought the watch)

2. I can't delete some of my mail for random reasons.

3. (This happened today.) I took my watch off the charger, and it was at 100%. Exactly 30 minutes later, it dies. I was so confused, but then it powered on and said it was at 10%! So I checked my battery in settings, it showed that it plumeted from 96% to 10%! I think it's because the maximum battery capacity was at 79% and it said "Service Recommended" below optimized charging.

4. My Walkie Talkie app does not allow me to talk to anyone.

5. I cant update my watch because it says "Unable To Check For Updates" (usually it says that when my mom does not update her phone because I'm using family sharing.) So its still at update 10.6.1

6. My cell service does not work sometimes and i will only get iMessages when im connected to my Wi-Fi.

7. My Mic is broken so i need to use my AirPods to talk or use dictation or i just put my lips on the Mic.

8. On my Apple Music i have a playlist and i deleted one of the songs, but it stays in the playlist. I cant delete it because I dont see remove from library or unfavorite. so all it does is just show the picture of the song but it plays nothing.

Can someone please tell me how to fix all of this, or i should just buy a new watch.