For words that have only 3 letters, there isn't any 4th letter. Such as with the word “insert”, there won't be any more letters afterwards and therefore need to be the word "insert". The word “addict” is while in the BIP39 wordlist however , you might have employed “addi” for https://bookmarkforce.com/story19119708/helping-the-others-realize-the-advantages-of-bip39-mnemonic-phrase-tool