For words that only have three letters, there isn't a 4th letter. As an example with the word “add”, there won't be any much more letters Later on and thus needs to be the word "incorporate". The word “addict” is in the BIP39 wordlist however, you would have made use https://bookmark-rss.com/story18700890/the-5-second-trick-for-ledger-seed-phrase-bip39