You can add reply buttons to your chatbot using this flow block:
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Click “add an option” to get started:
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Write the name of your button:
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Click on “+” to add a button:
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At this point a flow block will be created to create an action on the button you created:
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Click on the “Add an option” button to add another custom button, or click on the “+” button of the new block created to continue with your flow.