Air Pro 4. Left earbud loses charge much quicker

Hello.

I bought my EarFuns Air Pro 4 two days ago and I very much like them so far. But there is a proble with discharge speed between sides. I read that earphones have something like master/slave Sync technology and because of that left earphone can lose the charge quicker. But in this case the discrepancy in discharge is too big to simply assign to that technology.

Is there any solutions to that or it is just a defect?

Level of charge after about 6 hours of usage.