# 51005: Client Connection: Command or keepalive acknowledgement not received

Log Level: ERROR

## Description

### Possible causes

The client did not acknowledge a message or a keep-alive request, which is required by the connection protocol therefore the connection has been dropped. This is most often caused by network connectivity issues.

### Possible solutions

Twilio SDKs automatically recover and reestablish the connection if possible. For best user experience, ensure reliable network connectivity.