Examine these parameters settings: What is true about the control file?

When DB_CREATE_ONLINE_LOG_DEST_1 (and additional numbered destinations) are set, Oracle Managed Files automatically places one copy of the control file in each specified destination, resulting in a multiplexed control file across those locations.

DB_CREATE_ONLINE_LOG_DEST_n parameters take precedence over DB_CREATE_FILE_DEST for control file and online log placement, so a single control file residing only in DB_CREATE_FILE_DEST is not the outcome when the numbered destination parameters are also configured.

DB_RECOVERY_FILE_DEST defines the Fast Recovery Area and is not the primary destination for control files when DB_CREATE_ONLINE_LOG_DEST_1 is explicitly set, because the numbered destination parameters take precedence.

When DB_CREATE_ONLINE_LOG_DEST_1 is set and takes precedence, Oracle does not fall back to multiplexing across both DB_CREATE_FILE_DEST and DB_RECOVERY_FILE_DEST as a combined pair.