Battery level inaccurate BUT….

My Apple SE2 iWatch, just a month after I bought it, started shutting down at 60% battery and wouldn't start until it was connected to the charger again. Solutions posted on Apple discussion forums and communities and a workaround I tried accidently fixed the issue. 

A couple of days ago this issue re-occurred but none of the solutions that worked earlier helped this time. I put the watch on charge last morning and let the battery charge to 100% and quietly hoped that it would get back to normal functioning. It must have been 8 am when I removed it from charging. I wore my watch for more than 13 hours after charging and also ran its Workout app for 45 minutes in the evening. I used the Workout app once again this morning for 47 minutes. My watch's battery stayed at 100% for 24 hours, that is, till this morning. In the evening around 8pm, the watch shut down. I put it on the charger and checked the Battery widget on my phone after 10 minutes. It showed 24%. So the battery lasted 36 hours although I used the Workout app for 1.52 hours!

Apple claims that the iWatch SE2 battery lasts upto 18 hours. Once I thought the battery meter was not being refreshed to show the accurate battery level. I was wrong. If it was just the battery meter, my watch would have shut down late last night. BUT it ran much beyond its default capacity. 

Quite an unpredictable behaviour! Is there a way I could fix the battery issue for good?