Which day is this? If you go into the group chat and click a few times, then back to Daiki's chat it *should* unlock?
Let me know if 0.0.4c works for you - I suspect that somehow the Day 20 group chat has been partially skipped (probably worth checking that in the chat history and restarting from an earlier save if so) but this version should at least let you continue
0.0.4c: https://gofile.io/d/FVGAV9