一个文档保存到数据库后，Mongoose会产生冲突

I can't for the life of me figure out what simple thing I'm doing wrong here. I've widdled the user schema down to one property, name. When i post the first one to the database all is well and it is saved. When I try to save another one with a different name I get CONFLICT. It must be something super simple I'm missing but I need an extra set of eyes to check it out.I can't for the life of me figure out what simp