A format element was specified several times in the function TO_DATE.
In the format specification of the TO_DATE function, format elements were specified which must not occur together. For example, day of year (DDD) and Julian calendar date must not occur together. There must not be several specifications denoting the year, e.g. YYYY and YY, or the month, e.g. MM and MONTH.
Remove the format elements that are specified too often.
Remove one of the format elements that cannot occur together.