ORA-01855
AM/A.M. or PM/P.M. required
Cause
A date specification contained a meridian indicator format code but a valid meridian indicator was not specified. If a meridian indicator code, A.M., P.M., AM or PM, was included in a date format, the date must include a valid meridian indicator.
Action
Specify the meridian indicator in the correct format, A.M./AM or P.M./PM.