Airpods 4 (ANC) left bud charging issues

I have bought few days ago a new pair of Airpods 4 with ANC. My first pair of air pods paired with an iPhone. They

have this strange behavior. The left bud it charges till 100% in the case and after reaching the max power level, the charging stops and it start discharging inside the case (case closed!). From evening till next morning it loses 30-40% (10-12 hours). If the bud is taken from the case and put back in the case after 2-3 tries it will finally start to charge. It is very annoying and for sure not a normal behavior. The other bud is working just fine. It will be kept always to 100% inside the case after the charging to the max level is reached. Any ideas ?!