I probably read your post wrong but you mention that you set the PC version for Smartphone in your 2nd paragraph. So if it shows on Smartphone, it would appear that that is the intended result 🙂
Anyway, AdRotate (Pro) uses Mobile Detect to see which device is what. It’s a pretty good script but some newer devices may show up as something else. Some tablets identify as laptops for example. Lesser known brands may show wrong information as well.
So it’s not 100% accurate because of the devices themselves telling the wrong things. Maybe that’s what is happening for you.