It all depends on the definition of "reason"
The dictionary definition is:
A cause, explanation, or justification for an action or event.
This is not limited to physical reaction to a previous event. The cause of an event can be unidentifiable in physical terms, as quantum physics has shown.
'Unidentifiable', correct, in so far as it might not always be
easy to identify the prior reason for choices that we make. Sometimes we do things for no apparent reason, but it can be a problem of computation rather than a problem of concept to trace the line of cause and effect back through the unfathomably complex workings of a brain. Spare a moment to consider the computational magnitude underpinning what we experience as feelings and thoughts - it has been estimated that a human brain in a single second executes as many 'instructions' as the total digital computing resource of the entire planet as at 2007 with 100 trillion data points in cache memory. So it is not easy and simple to trace the line of cause and effect through the workings of a mind
'Unidentifiable', in the sense that there may be some truly random element in the mix thanks to some base aspect of quantum reality, perhaps we can't rule that out but if that is the case then the resulting choice is also random.
A choice is either due to cause and effect or it is random; take your pick
So if a conscious choice is initiated by the spiritual soul, it will indeed have a reason, but not necessarily caused by a previous physical event.
Invoking some or other unevidenced make-believe makes not a jot of difference to the issue. I am writing these words now not because I want to but because my pet magic dragon told me to and he knows everything and he really wanted me to write them for reasons unknowable to me. All I am doing here is routing my chain of cause and effect through some alleged other realm of reality and that is all you are doing too. A choice is still the determined outcome of a chain of cause and effect or it is random; take your pick.