For words that have only 3 letters, there is not any 4th letter. Such as with the word “incorporate”, there isn't any a lot more letters Later on and therefore should be the word "insert". The word “addict” is while in the BIP39 wordlist but you might have used “addi” https://whitebookmarks.com/story19532414/how-much-you-need-to-expect-you-ll-pay-for-a-good-bip39-definition