What does it mean when an “Er7” message appears?

Er7:
1. CareSens N NFC: This error is displayed when there are defects with NFC function.
→ If the problem persists, contact the Customer Service Center at csteam@i-sens.com.
2. CareSens N Voice: When abnormal current is defected during self-check. In case foreign liquid inflow or humidity inside the meter.
→ If the problem persists, contact the Customer Service Center at csteam@i-sens.com.