To check and resolve above problem Oracle Application has a script named afshrchk.sql avilable in $FND_TOP/sql directory.

This script checks requested table.columns for invalid trailing spaces and control characters. This script can also be used to
remove trailing blanks and control characters. It is recommended to run this script first without stripping prompt to make sure
all detected values really should be fixed.

Display Message/Exception on the Form from Database Trigger

Use the Raise_message function of ax_message to display a message/exception on a form from Database Trigger.

apps.ax_message_pkg.raise_message
        (
        'AX',  --Use Value 'AX' for this parameter
         'AX_56000_COMM_TRIG_EXCEPT', -Message Name Use value 'AX_56000_COMM_TRIG_EXCEPT' for this parameter
        'TRIGGER_NAME', - Token Name 1
        'CYCLE_COUNT_ENTRIES_TR1', -Token Value 1
        'ERROR',       Token Name 2
         v_error_message Token Value(Error Description)
        );

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