This is most likely because the ear buds are not charging when put in the case caused by a disconnection somewhere. It could be inside of the buds themselves but are more likely because of the case.
The buds needs to be pushed down onto the charging pins which have been an issue for my pair before for others if the magnets which hold the bud in place are giving up or if there is a build up of grease or ear wax which prevents them.
Jabra explain [link|https://www.jabra.com/support/export/faq?pdf=1&shareUrl=https://www.jabra.com/supportpages/jabra-elite-75t/100-99090001-02/faq/6d2dd9a9-45ec-4b5e-94e5-55360dd52226&id=6d2dd9a9-45ec-4b5e-94e5-55360dd52226&groupid=1491|how you best clean you in ears|new_window=true] and a [link|https://www.youtube.com/watch?v=TFhZG8stUbs|youtube video|new_window=true] shows a fix to counter the faulting magnets using some tissue paper.