Hello Artur,
You may want to configure the initial welcome message using Architect's Send Response action in your inbound message flow before your Call Digital Bot Flow action. This should help ensure the flow is triggered correctly from the first message rather than requiring a second message to activate the bot.
If the issue persists after trying that, I would suggest opening a case with Product Support and providing a sample Conversation ID for further investigation.
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Jason Kleitz
Online Community Manager/Moderator
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