how can I delete "cancel" reservation entry type Reservation Surplus?
What do you mean? Do you want to remove the ability for users to cancel surplus reservation entries? Or do you need to delete a specific reservation entry of the type surplus already in your database?
I need to delete a specific reservation entry of the type surplus already in the database when I post Inventory Journal
Ok, we need a bit more information. Exactly what is your requirement?
Why do you need to delete it? What have you tried before? Have you tried deleting it via reservation entries before you post the journal?