If your company code status is changed in your production system to "legacy data migrated", then you may not post OASV Journal. If you are in test / development clients, still you can use it.
Otherwise, please use transaction code AFB1 to post the entries.
For debit use posting key 70 and credit posting key 75, then give the account (which must be a reconciliation account)
If it is non-reconciliation account, then use posting keys 40 and 50.
Kind Regards,
Ravi