Voice Memos as Music

I have an iphone 6plus running ios 11.2.2

I have manually added voice memos from my phone to my itunes music. They show up on my lap top under my music. I can play them on my laptop as music. I have made a play list with the voice memos on my laptop. That all works great. I wanted to add this play list to my phone so it will play over my radio in my vehicle while driving. I have checked the box and synced with my phone. I have tried dragging th