Oracle Message ORA-19694 - some changed blocks were not found in the change tracking file

ERRORsome changed blocks were not found in the change tracking file
CAUSEA backup or copy found that some changed blocks had not been recorded in the change tracking file. The details of which files and blocks are affected will be in an Oracle trace file.
ACTIONThis indicates that there is a problem with the change tracking feature. Disable change tracking and re-start the backup.