the problem is caused by the logical condition Time = 'Month'. When it's used in the Monthly chart, it renders True only for selected (or available) Months, and it renders False for the excluded (unavailable) months. So, when it's False, it looks like the selection of Months is ignored, when in fact it's just the condition that doesn't work correctly.
The fix is rather simple: replace your existing conditions with this:
only(total Time) = 'Month'
and everything will work correctly.
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