NULL Column in an Aggregate Function Warning

Within the PL/SQL editor within Oracle Forms I am running the following code:

select COUNT(*) INTO v_record from MMLD.mariner_doc_type_info where mariner_doc_type_info_id = v_info;

                    IF v_record = 0 THEN

insert into MMLD.mariner_doc_type_info(MARINER_DOC_TYPE_INFO_ID,DOC_TYPE_DESC, ACTIVE,DOC_TYPE_CODE) values(MMLD.mariner_doc_type_info_id_seq.nextval,v_desc,v_active,v_code );

                            commit;

I am receiving the warning " ORA-24347: Warning of a null column in an aggregate function." Then the insert statement fails to run.

I need to know if this is a known issue and if there is a known workaround.