PL/SQL table question

I have a two PL/SQL tables; I am trying to create a string. Inside the loop for the first table, I get the values for the second table and concatenate the two to form a string.

The problem I am facing is that the last value of the first loop is being repeated after the last loop! Has anyone faced this problem and how did you get around it - would be very interested to know.

Thanks,
IB

Code:

   WHILE j <= l_resp.LAST

    LOOP -- resp loop
    dbms_output.put_line(l_resp(j).data_string||v_step);

      i := l_country.FIRST;
      v_step := 4;
     WHILE i <= l_country.LAST -- country loop
     WHILE i IS NOT null -- country loop
     LOOP
    dbms_output.put_line(l_resp(j).data_string||v_step);
     END LOOP;