EM 13c Cloud Contorol Login Fails as SYSMAN with Error: oracle.sysman.emSDK.sec.auth.InvalidEMUserException: Failed to login using repository authentication for user: SYSMAN

Issue:

Failed to login using repository authentication for user: SYSMAN
oracle.sysman.emSDK.sec.auth.InvalidEMUserException: Failed to login using repository authentication for user: SYSMAN

Cause:

Unable to extend MGMT_TABLESPACE  tablespace.

Solution:

Add datafile or resize existing datafile in MGMT_TABLESPACE  tablespace.