Table name:ch_pwd block:ch_pwd
 
employeeid,old_password,new_password,confirm_new_password
 
Table name:emp_login
employeeid,password

Table Name:ch_pwd,emp_login
 
UPDATE emp_login A
SET password = (SELECT new_password FROM ch_pwd WHERE EMPLOYEEID = A.EMPLOYEEID);

UPDATE emp_login
        SET password = ( SELECT password
                    FROM ch_pwd
                    WHERE emp_login.employeeid = ch_pwd.employeeid)
               
               WHERE EXISTS
          ( SELECT password
                    FROM ch_pwd
                    WHERE emp_login.employeeid = ch_pwd.employeeid);

UPDATE emp_login A SET 
  password = (SELECT new_password FROM ch_pwd WHERE EMPLOYEEID = :your_data_block.EMPLOYEEID)
  where employeeid = :your_data_block.employeeid;

update emp_login set
  password = :your_data_block.new_password
  where employeeid = :your_data_block.employeeid;

UPDATE ...
SET ...
where employeeid = :your_data_block.employeeid;   --> you are missing this line