Hi Azael,
We use collections of integers, decimals, dates, currencies etc in bot flows without issue.
A statement like Flow.cardNumber[0] or GetAt(Flow.cardNumber, 0) in a communicate action will error out if the list is empty.
I suggest you put a check in for IsNotSetOrEmpty(Flow.CardNumbers) then set a flag or play a prompt - at least for testing to see if this is the case.
Or you can try something like If(IsNotSetOrEmpty(Flow.CardNumbers),"No Cards on this account",ToString(GetAt(Flow.CardNumbers, 0)))
At least as a starting point to confirm if the list is empty or not when processed by Architect, which does flatten the DataAction output, so also suggest when testing the DataAction you flatten the output, as this is what Architect will see.
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Anton Vroon
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