Oracle Error Message
ORA-31540: string is not a valid identifier
Reason for the Error
All Change Data Capture (CDC) identifiers must have at most 30 characters, and must start with a letter that is followed by any combination of letters, numerals, and the signs ‘$’, ‘_’, and ‘#’. Other characters cannot be used in identifiers. The rules for CDC identifiers are the same as for PL/SQL identifiers.
Solution
Rename object to conform to CDC naming rules and try again.