Hi Irfan Wazir,
Thank you for posting in the Microsoft Community Forums.
Check network connectivity:
Ensure that the network connections between all servers are working and that no firewalls or routing rules are preventing the synchronization operation.
Check synchronization settings:
Recheck the settings of the synchronization software to make sure that the paths to the source and destination folders are correct, and that the synchronization options (e.g., synchronization frequency, synchronization method, etc.) are set correctly.
Check the log files:
Check the log files of the synchronization software to find possible error or warning messages, and troubleshoot and solve the problem according to the log prompts.
Best regards
Neuvi