Hi there,

Based on your description, it appears the internal battery has reached the end of its lifecycle and can no longer hold a charge.

Please note that our sensors generally carry a two-year warranty. As your units are now beyond this period, they may no longer be eligible for a free replacement.

However, you can still contact our support team at support@netrohome.com. Even for out-of-warranty devices, our technical team is happy to perform a final assessment and can provide you with the best available options.

Best regards,

Netro Support Team