For words that have only 3 letters, there is not any 4th letter. By way of example with the word “include”, there aren't any a lot more letters Later on and thus should be the word "incorporate". The word “addict” is inside the BIP39 wordlist but you would've utilised “addi” https://thesocialvibes.com/story4281830/the-ultimate-guide-to-bip39-seed-phrase-github