For words that have only 3 letters, there isn't a 4th letter. For example with the word “add”, there won't be any more letters Later on and therefore should be the word "insert". The word “addict” is inside the BIP39 wordlist but you might have made use of “addi” for https://bbsocialclub.com/story20740561/5-essential-elements-for-bip39-explained