For words that have only 3 letters, there's no 4th letter. One example is with the word “include”, there won't be any extra letters Later on and thus needs to be the word "incorporate". The word “addict” is during the BIP39 wordlist however, you might have utilised “addi” for “addict”. https://hotbookmarkings.com/story18966320/new-step-by-step-map-for-ledger-seed-phrase-bip39