merge replication issue

Hi Team,

i am new to replication we have merge replication in my environment we are getting below error in replication monitor subscriber server,any one help me out how to resolve the issue 

Error messages: The merge process was unable to create a new generation at the 'Publisher'. Troubleshoot by restarting the synchronization with verbose history logging and specify an output file to which to write. (Source: MSSQL_REPL, Error number: MSSQL_REPL-2147200994) Get help: http://help/MSSQL_REPL-2147200994

Regards,

Nasar.