Oracle Message PLS-00338 - unable to resolve string as a column or row expression

ERRORunable to resolve string as a column or row expression
CAUSEYou have a reference to a name that could not be resolved as a column or row expression. This occurred in an update or insert statement involving an object-table.
ACTIONIf this is an update statement and you intended to code this as a column reference, fix it as such. If you intended to code this as a row expression, change this to refer to an alias of an object-table.