XPS 15 9510 Sleep issues

My XPS 15 9510 laptop is having sleep issues again.....

Specifically, I expect my laptop to go sleep and stay asleep when the lid is closed.  Unfortunately, it has a tendency to wake up closed and in my backpack.  This ends up draining the battery overnight, so after a single night of not using it, it's completely drained in the morning.  

Past Dell laptops have not done this, so I am sorely disappointed to have bought a premium priced laptop and have gotten such a shoddy product. 

Has anyone found a way to get this laptop to work as expected?