programming a new key

I have got a Griso 1100 and I’m trying to programme a new key. I have the 12425 code but I need to enter another code. Any advice please?

Do you have a working original key? If so you can get a key cloned and cut at any Timsons for about £30. I did this when the previous owner of my Griso could only supply one key. No codes to enter at all.