cancel and back buttons best practices in chat bot design telegram

I building a chat bot for ordering food and need to ask some information from user:

  1. Product type
  2. Product quantity
  3. Delivery address
  4. Delivery date
  5. Delivery time

When user selected a product type chat bot should ask for quantity and so on. But the user could make mistake on any step. How can I make functionality to undo/edit last interaction?

There are some alternatives:

  1. Back button on each step
  2. Edit button on last (intermediate) confirmation step

With back button chat history will be looked like this:
Bot: what would you like to do? (main menu: make order, my orders etc.)
User: make order
Bot: select a product type
User: product A
Bot: enter a quantity
User: back (is product A should not be selected after this interaction?)
Bot: select a product type
User: back (what a bot should do?)

With edit button we need to make ability to cancel editing like this:
Bot: Is this information right?
User: No, edit
Bot: What would you like to edit?
User: Product quantity
Bot: enter a new quantity
User: Cancel (what a bot should do?)