How do I edit a poll?
You can edit the question of any poll via the "Details & More" menu, which you can get to via the "..." button like so:
Editing options on a poll is not currently supported, so a workaround is to delete and recreate the poll. Before you delete it, you can copy the /poll command from the same “Details & More” screen:
Once you’re ready, you can delete the original poll from the same "..." button, and then "Delete Poll".