Clean your charging case with a suitable cloth or an alcohol cleaning pad
There should be no obstruction in the charging case stopping the earbud from being properly seated. Be sure to remove any obstruction or debris from the charging case, as well as on and around the charging contacts. If there is sweat, liquid or obstruction on the charging contacts within the case, corrosion may occur. In this situation, please clean the charging terminal or earphones with a suitable cloth or alcohol cleaning pad before charging. Cotton buds can also be used to get into the charging case to gently clean around the charging pins and remove any obstructions.