For words that only have 3 letters, there is no 4th letter. As an example with the word “include”, there are no much more letters Later on and thus should be the word "increase". The word “addict” is from the BIP39 wordlist however , you would have used “addi” for https://wisesocialsmedia.com/story4907508/the-greatest-guide-to-seed-phrase-bip39