OpenJPA: org.apache.openjpa.persistence.ArgumentException

I am getting the below exception while mapping jpa entities.

org.apache.openjpa.persistence.ArgumentException: "com.abc.P1.e1" defines a target of "cd" for column "p_cd", but that target does not exist in table "E1"

I am using multi column FK & have defined the join columns as mentioned below. Please note that cd & ab columns are present in the table E1. They are also foreign keys to other entities(Test1 & Test2) separately. The unique key is also present for combined cd and ab columns in table E1.

could anyone please help to understand what I missed here? Thanks in advance!

@Entity
public class P1 ...{
...
     @OneToOne(fetch= FetchType.LAZY)
        @JoinColumns({
                @JoinColumn(name="p_cd", referencedColumnName="cd"),
                @JoinColumn(name="p_ab", referencedColumnName="ab")
        })
        private E1 e1;
...
}

@Entity
public class E1 ... {

    @Id
    private long e1_id;

...
    @ManyToOne
    @JoinColumn(name = "cd")
    private Test1 t1;

    @ManyToOne
    @JoinColumn(name = "ab")
    private Test2 t2;
...
}