LINE Flex Messages are messages with a customizable layout. You can customize the layout freely based on the specification for CSS Flexible Box (CSS Flexbox) LINE provides a Flex Message Simulator that you can use to check the layout of your message.
LINE Flex Message is not a message type in Conversation API but it is possible to send Flex Message by overriding with Explicit Channel Message.
To do that, you can follow these steps:
Another alternative is to use another message type provided by the Conversation API. Sinch provides a Message Composer tool on the dashboard that would help you to easily build a message and visualize it in any social channels provided by the Conversation API.
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