在包内调用Oracle SQL(PL SQL)过程会返回错误

我正在尝试创建一个包,其中包含在表中插入行的过程。

包标题:

CREATE OR REPLACE PACKAGE pkg_developers
AS
    PROCEDURE empty_tables;
    PROCEDURE add_city(country IN CITIES.COUNTRY%type, zipcode IN CITIES.ZIPCODE%type, city IN CITIES.CITY%type);
END pkg_developers;

包体:

CREATE OR REPLACE PACKAGE BODY pkg_developers AS

    PROCEDURE empty_tables
    IS
    BEGIN
        EXECUTE IMMEDIATE 'TRUNCATE TABLE cities CASCADE';
        /* More truncate statements*/
        DBMS_OUTPUT.put_line('Tables truncated successfully.');
    END empty_tables;

    PROCEDURE add_city(p_country IN cities.COUNTRY%type, p_zipcode IN cities.ZIPCODE%type, p_city IN cities.CITY%type)
    IS
    BEGIN
        INSERT INTO CITIES(COUNTRY, ZIPCODE, city) VALUES(p_country, p_zipcode, p_city);
        COMMIT;
    END add_city;

END pkg_developers;

我如何执行程序:

BEGIN
    pkg_developers.empty_tables();
    pkg_developers.add_city('Country', '1111', 'City');
END;

我得到的错误是:

[2022-04-16 11:41:48] [72000][4063]
[2022-04-16 11:41:48]   ORA-04063: package body "PROJECT.PKG_DEVELOPERS" has errors
[2022-04-16 11:41:48]   ORA-06508: PL/SQL: could not find program unit being called: "PROJECT.PKG_DEVELOPERS"
[2022-04-16 11:41:48]   ORA-06512: at line 2
[2022-04-16 11:41:48] Position: 0
[2022-04-16 11:41:48] Summary: 1 of 1 statements executed, 1 failed in 15 ms (106 symbols in file)

我确实发现如果我删除了程序的参数 add_city 对这些值进行硬编码确实有效,但我一辈子都搞不清楚这些参数会有什么问题,我在网上看过一些例子,它们似乎和我一样。

我也尝试调用完全相同的过程,但不在包内,然后它也可以正常工作。