Whenever a checksum is invalid, alert the person the phrase is not something created by your app, and ask whenever they would like to use it anyway. In this manner, your app only really should hold the wordlists for your personal supported languages, however, you can recover phrases made by https://sb-bookmarking.com/story18971892/helping-the-others-realize-the-advantages-of-bip39-mnemonic-phrase-tool