For words that only have 3 letters, there isn't any 4th letter. By way of example with the word “increase”, there aren't any more letters Later on and so have to be the word "insert". The word “addict” is inside the BIP39 wordlist however , you would have made use https://7prbookmarks.com/story19009275/top-latest-five-bip39-seed-phrase-mnemonics-generator-urban-news