Hi there,
Unless the apartment house regulations forbid smoking, your neighbor has the right to smoke legal substances. However, if the smoke or smells generated by their smoking habit prevents you from using your balcony or opening your windows, you can complain to your landlord or the building's adminsitration. They will issue a series of warnings and, if the practice continues, possibly evict your neighbor from the building.
Best regards from Moneyguru
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