I’ve had those earbuds for a while now and never had such a major issue.
I charged them overnight, the left earbud works completely fine, but right one isn’t being seen by the bluetooth nor app, its like it is offline.
although it keeps flashing and showing white light when it is inside the case.
I tried resetting and reconnecting, nothing worked, i cleaned my case with a dry cotton completely. Still, nothing.
I would contact Soundcore Support at service@soundcore.com. Hopefully they have a suggestion or two.
Do the contacts look corroded? I’ve had this issue with other earbuds where despite the contacts being clean, there was corrosion and couldn’t make good contact with the case.
When you open the case most times it will be to tell you the charge of the battery (1, 2 or 3 lights) but when you are closing it the first and 3rd should light up at the same time or potentially separately to show that each earbud is charging.
If both are showing then it could be something else such as an issue with the BT or etc…