I was trying to find out why my laptop would fail on battery when the battery status showed that 95% available and several hours of charge remaining. I found the command-line program powercfg and looking at the results it generated I found that some of my USB devices wouldn't allow the system to sleep. I didn't find my battery issue but this may find what could be preventing your computer from sleeping.

https://www.tenforums.com/tutorials/5148...ndows-10-a.html