This can happen for several reasons:

1. Press the button on the side of the power  to ensure the charging mode is activated.
   
2. Check that the battery connector is properly inserted into your phone.
   
3. Make sure the charging port of your phone is not clogged.
   
4. It is possible that the overheat safety mechanism was triggered. On rare occasions, during the summer, charging stations placed near a window or outdoors can be subjected to intense heat. In such cases, to prevent overheating, the protective mechanism may temporarily block the battery, and it will not charge your phone.
   
   If less than 5 minutes have passed since the rental started, simply return the battery to any available slot: the rental will be canceled, and the previously pre-authorized amount (deposit) will be fully refunded.
   
   If you find that the battery does not charge after the free five-minute period has passed, please return the battery to any available slot and contact us via WhatsApp (+34 682 68 26 56) or email ayuda@firevolt.com. We will be happy to assist you!