For words that have only 3 letters, there is not any 4th letter. Such as with the word “insert”, there isn't any a lot more letters afterwards and so need to be the word "add". The word “addict” is during the BIP39 wordlist however, you would have utilised “addi” for https://dirstop.com/story21911572/facts-about-bip39-seed-phrase-word-list-revealed