please show me what I am doing wrong, I am confused

this is oracle 19c sql developer

e create procedure add_shipment_method (in sm_id int, in _name varchar (20) Begin insert into shipment method (shipment_method_id, shipment_description) values (sm_id, e_name); BND call add shipment_method (12, 'Sea'); select from shipment_method; I create or replace trigger Check_Availability before or after insert on product for each row update or delete Query Result x Script Output x Task completed in 0.434 seconds Error starting at line: 31 in command create procedure add_shipment method (in sm_id int, in s_name varchar(20)) Begin insert into shipment method (shipment method_id, shipment_description) values (sm_id, s_name); call add_shipment method (12, 'Sea'); select from shipment method; Error report ORA-00955: name is already used by an existing object 00955. 00000 "name is already used by an existing object" *Cause: Action: Create a stored procedure named Add_Shipment Method that lets a user insert new shipment method to the shipment method table in the database. This procedure should have two parameters, one for each of the two columns in this table. Then, include the following test statements after the procedure in your submitted script file. CALL Add_Shipment Method (12, 'Sea'); Select * From Shipment Method; (Note that this table doesn't allow duplicate record) 1and