For words that have only 3 letters, there isn't any 4th letter. For instance with the word “incorporate”, there isn't any additional letters afterwards and therefore must be the word "insert". The word “addict” is from the BIP39 wordlist but you might have used “addi” for “addict”. By next the https://bookmark-search.com/story18726485/ledger-seed-phrase-bip39-no-further-a-mystery