For words that only have three letters, there is not any 4th letter. Such as with the word “insert”, there won't be any far more letters afterwards and therefore has to be the word "add". The word “addict” is inside the BIP39 wordlist however, you would have utilized “addi” for https://sound-social.com/story8819401/helping-the-others-realize-the-advantages-of-bip39-seed-phrase-mnemonics-generator