For words that have only three letters, there isn't a 4th letter. One example is with the word “insert”, there are no more letters Later on and therefore have to be the word "increase". The word “addict” is from the BIP39 wordlist however , you might have utilized “addi” for https://minibookmarking.com/story19587136/5-simple-techniques-for-bip39-word-list-pdf