ORA-04098: trigger 'BRANCH_MOVE' is invalid and failed re-validation. Any ideas ?

I have created (without any compilation errors) a trigger but when actioned I get a ORA-04098 error.
The manual says to drop or disable the trigger but that doesn't help me. Does anyone know what I am doing wrong.

create or replace trigger branch_move
after
update of association_id on person
for each row
begin
insert into branch_movement

        values (:new.id, :new.association_id, 'NEW', sysdate); end;

Many thanks

Robin Received on Thu Jun 10 1999 - 03:06:33 CDT