Errors with post-insert trigger

Question

I had a POST-INSERT TRIGGER here.but i encountered some problems.can someone help me with the errors?
begin
     insert into user_acct
     userid_n, user_m, coy_c, contact_n, emp_n,
     work_loc_c, curr_passwd_t, prt_f, indv_pc_f, pc_deploy_c,      
     ext_email_addr_t, other_na_sys_t, status_c, status_rmk_t, upd_d)
     values
     (:user_acct.userid_n, :user_acct.user_m, :user_acct.coy_c, :user_acct.contact_n, :user_acct.emp_n,
     :user_acct.work_loc_c, :user_acct.curr_passwd_t, :user_acct.prt_f, :user_acct.indv_pc_f, :user_acct.pc_deploy_c,                
     :user_acct.ext_email_addr_t, :user_acct.other_na_sys_t, :user_acct.status_c, :user_acct.status_rmk_t,                
     :user_acct.upd_d);
     exception
          when others then
               clear_message;
               Message('Insertion of Applicant Particulars failed');
               SYNCHRONIZE;
               RAISE Form_Trigger_failure;
end;
begin
insert into user_acct_na_detl
     na_sys_c)
     values
     (:na_sys_cd.na_sys_c);
     exception
          when others then
               clear_message;
               Message('Insertion of Non-Application failed');
               SYNCHRONIZE;
               RAISE Form_Trigger_failure;
end;
          when others then
               null;      
end;     
the error:
Error 103 at line 31, column 3
Encountered the symbol 'WHEN' when expecting one if the following:
begin declare end exception exit for goto if loop mod null
pragma raise return select update while <an identifier>
<a double-quoted delimited-identifier><a bind variable><<
close current delete fetch lock insert open rollback
savepoint set sql commit<a single-quoted SQL string>
The symbol "exception"was substituted for "WHEN" to continue
Error 103 at line 2, column 1
Encountered the symbol "END"

Answer 1

i delete the "END" already but when i compile again, i encountered some error again.
Error 370 at line 27, column
OTHERS handler must be last among the exception handlers of a block
Error 0 at line 1, column 1
Statement ignored