I already set the debug type in IP phone before to get the log but after export still get nothing.

Hello, owencl!
Welcome to our community!

Please try to clear the logs first before you set it to debug.

Thanks!

Important

Unified logging is available in iOS 10.0 and later, macOS 10.12 and later, tvOS 10.0 and later, and watchOS 3.0 and later, and supersedes ASL (Apple System Logger) and the Syslog APIs. Historically, log messages were written to specific locations on disk, such as /etc/system.log. The unified logging system stores messages in memory and in a data store, rather than writing to text-based log files.