In my company I have two servers one is like abc and second one is xyz, both are in cluster. When my abc server is down it automatically route to xyz server, but now I am getting an error like unable to replicate with the server xyz and special database object cannot be located.
As Simon stated in the comments, the error messages like "special database object cannot be located" or "RRV bucket is corrupt" are directly related to a cluster failover event.
Verify that all your mail database replicas (on server abc AND server xzy AND locally on the PC) are not damaged or corrupt. If one or more replicas give a "RRV bucket is corrupt" error, replace them with a new replica from a working instance or a backup.
If that does not fix your problem, please give more details like Server version, client version, output of "fixup" and "compact" on all database replicas, ...