Hello @Marcus Wong Theen Nam
I would recommend the next post as initial troubleshooting: https://social.technet.microsoft.com/Forums/lync/en-US/aaadde63-a2c1-4128-8d11-f94d2453f6a2/dfsr-member-is-waiting-for-initial-replication-for-replicated-folder-and-is-not-currently?forum=winserverfiles
Please do share any future findings for the community to provide more specific ideas,
Hope this helps with your query,