RMAN-03008 / RMAN-20020 Issue when registering to rman catalog db | Oracle Database

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If you run into an Issue like below when register database with catalog

rman

connect catalog user/pwd@RMAN_cat

connect target /

RMAN> register database;

starting full resync of recovery catalog

full resync complete

database registered in recovery catalog

RMAN-00571: ===========================================================

RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============

RMAN-00571: ===========================================================

RMAN-03008: error while performing automatic resync of recovery catalog

RMAN-20020: database incarnation not set

exit

Solution:

rman

connect catalog user/pwd@RMAN_cat

connect target /

unregister database;

register database;

exit