Hi khann kosal,
Synchronizing state mean that the principal server is sending log records to the mirror server, the mirror is trying to catch up. Please check the Database Mirroring Monitor as Uri mentioned. Expand Databases, and select the database to be monitored. Right-click
the database, select Tasks, and then click Launch Database Mirroring Monitor.
If you have any progress, please share us the result.
Best regards,
Cathy
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