For words that have only three letters, there isn't a 4th letter. Such as with the word “incorporate”, there are no extra letters Later on and thus need to be the word "incorporate". The word “addict” is in the BIP39 wordlist but you might have utilized “addi” for “addict”. You https://thebookmarkid.com/story19037727/the-5-second-trick-for-ledger-seed-phrase-bip39