Cannot execute stored procedure in Oracle19c

I am currently facing an issue(below is the error code) when trying to import data from a .csv file to OracleDB. Now, I have a stored procedure so that I could easily call it out. Now, every time I try to run or call the stored procedure it gives me an error(error code below)

So this is my stored procedure called load_csv_into_employee;

CREATE OR REPLACE PROCEDURE load_csv_into_employee AS
   v_count NUMBER;
BEGIN
   DBMS_OUTPUT.PUT_LINE('Checking if the external table already exists...');

   -- Check if the external table already exists
   SELECT COUNT(*)
   INTO v_count
   FROM user_tables
   WHERE table_name = 'CSV_TABLE';

   -- If the external table doesn't exist, create it
   IF v_count = 0 THEN
      DBMS_OUTPUT.PUT_LINE('Creating the external table...');
      EXECUTE IMMEDIATE '
         CREATE TABLE csv_table (
            EMPLOYEE_ID VARCHAR2(50),
            FIRST_NAME VARCHAR2(100),
            LAST_NAME VARCHAR2(100),
            DEPARTMENT VARCHAR2(200)
         )
         ORGANIZATION EXTERNAL (
            TYPE ORACLE_LOADER
            DEFAULT DIRECTORY csv_dir
            ACCESS PARAMETERS (
               RECORDS DELIMITED BY NEWLINE
               FIELDS TERMINATED BY '',''
               MISSING FIELD VALUES ARE NULL
            )
            LOCATION (''mssql_data.csv'')
         )';
   END IF;

   -- Insert data into EMPLOYEE
   DBMS_OUTPUT.PUT_LINE('Inserting data into EMPLOYEE...');
   EXECUTE IMMEDIATE '
      INSERT INTO EMPLOYEE
      SELECT * FROM csv_table';

   -- Drop the external table
   DBMS_OUTPUT.PUT_LINE('Dropping the external table...');
   EXECUTE IMMEDIATE 'DROP TABLE csv_table';

   DBMS_OUTPUT.PUT_LINE('Committing changes...');
   COMMIT;
EXCEPTION
   WHEN OTHERS THEN
      DBMS_OUTPUT.PUT_LINE('Error: ' || SQLERRM);
END load_csv_into_employee;
/

However it gives me this error every time I execute it: Error: ORA-29913: error in executing ODCIEXTTABLEOPEN callout.

I tried(Most of the answers I searched they based on permission issue):

1. I have tried researching here and found that there might be a permission issues. So I made sure that I have created the csv_dir using the syntax CREATE DIRECTORY csv_dir AS '\\dir\path\your_file.csv'; and also made sure that I have granted it with permission. GRANT READ, WRITE ON DIRECTORY csv_dir TO MyUserName;. I used the sys as sysdba user to grant permission for this one

Note: I am currently just trying to test and learn so I had to use the SYS user.

EDIT: I have added print on every execution, so it stops on the Inserting data into EMPLOYEE and then the error shows up.