For words that only have 3 letters, there isn't any 4th letter. For instance with the word “insert”, there won't be any far more letters afterwards and so need to be the word "insert". The word “addict” is while in the BIP39 wordlist however you might have utilized “addi” for https://bookmarkmiracle.com/story20523229/invalid-bip39-phrase-things-to-know-before-you-buy