There could be several reasons for this. Here are some things to check:
• Not enough time for battery to be activated/”charged” after removal of the tab.
• Dented battery surface causes poor contact with battery terminal of the hearing aid.
• Battery is dead (even if it is brand new). This is very rare. Can as well happen when not activated correctly!! Built up dirt on the battery terminal of the hearing aid causes poor contact.
• The battery does not fit into the battery door of the hearing aid (some battery doors are designed with a smaller cavity where the battery negative housing is placed).
lf hearing aid does not work properly after replacing with a new battery (wait two minute after removing the tab before use),If this does not help please take your hearing aid to your hearing care provider for further troubleshooting.