For words that have only three letters, there is absolutely no 4th letter. For instance with the word “add”, there isn't any much more letters Later on and so should be the word "increase". The word “addict” is in the BIP39 wordlist however , you would have utilized “addi” for https://hylistings.com/story19930781/a-secret-weapon-for-bip39-words-to-numbers