According to the documentation, Tasks can be created relative to a Contact (Subscriber), Deal, or Neither. The type of relationship being referenced should be specified by the dealTask.reltype parameter.
I am finding that this parameter is ignored, and I get a message saying “The related deal does not exist.” when I try to use reltype = Subscriber or no reltype.
It is also not clear whether reltype should be blank or missing, or whether it matters, in the Neither case.
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