Series 6 watch constantly displays 1% battery life even after being fully charged.

I got my Apple Watch Series 6 in February. Shortly after getting it, I’ve observed two things:

1) The watch would frequently black out and the apple logo would appear on the screen for about 2 minutes; and

2) The watch displays a battery life of 1% even after I fully charge it.

I have tried force restarting the watch and updating the software but the problem persists.

Please help :(