Bluetooth 5.1 or 5.4?

It's not clear

Got this on January 2023. Its November 2024 as I'm writing this and these have been awesome. Excellent sound, excellent battery. I noticed the battery doesn't last as much as when I got it but I'm still getting 4+ hours of playtime even after nearly 2 years of buying this.

It works fine in the beginning but after months use battery drains quickly and doesn't even last one hour ...
Sound quality is awesome though...

I bought it Nov 2023. It was working really well. Then, this June 2024, the other earbud doesn’t work anymore. I tried to hard reset like the video, it’s still not working

they didnt work