Remove error code

Author: manikantsinghms

concepts/backup-storage-error-codes.md

@@ -58,7 +58,6 @@ The following table lists the possible error and response codes that can be retu
 
 | HTTP status code| Error code| Error message | Description|
 |:------------------|:--------------|:--------------|:--------------|
-|200|ProtectionUnitAlreadyExists|This is a delta patch ProtectionUnit level error returned when the request has duplicate Protection Unit in the list that is already present in the service.|ProtectionUnit level error: ProtectionUnit already exists.|
 |200|ProtectionUnitNotFound|This is a delta patch ProtectionUnit level error returned when the user requests to remove Protection Unit, which isn't present in the service.|ProtectionUnit level error: ProtectionUnit doesn't exist.|
 |400|DuplicateProtectionUnitInList|This is a Protection Unit level error returned when the request has duplicate artifacts in the list.|Protection Unit level error: Duplicate Protection Unit in list.|
 |404|PolicyNotFound|Thrown when the ID is valid but the policy doesn't exist.|Unable to get the Protection Policy.|