I have the Dell XPS 13, i5, with the Win 10 OS (64 bit) - just got it not long ago.
When I put the laptop on Sleep Mode (Either if I close the lid, or if I do it from the "Start Menu" and choose the "Sleep" option), the Laptop goes to sleep, and then wakes up immediately (after 2-3 seconds) with no apparent reason. If I immediately try to make it "sleep" again, it wakes up again after 2-3 seconds. It is like it refuses to sleep. The only way to fix it, is to restart the laptop, which sometimes fixes the problem, only until it happens again - and I notice too late when my battery is empty.
It deprives me of relying on the Sleep Mode, which is really 50% of the user experience on a SSD laptop.
How can I fix this?
Put it to sleep with the lid open. After it wakes, open an admin command prompt and type the following.. Let us know what it says.
I suppose I should add, just in case, you might also run the powercfg -requests to see if something is keeping it awake... Many times it is the network traffic.
I've had a similar issue with the XPS 15 9550. It appears to have been caused by failure to hibernate after a pre-set time of sleep. Subsequently, attempts to sleep, hibernate, or even software shutdown, would result in instant waking a couple of seconds later. Normality would be restored after a hard shutdown (5 sec off button), until the next longer period of sleep.
So, try opening Power options, Change plan settings, Change advance power settings, expand Sleep, set "Hibernate after" to Never; Wake timers: disabled on battery, Only important on AC power. I've also disabled Hybrid sleep, however some claim it works.
Some also recommend disabling Fast boot. I did it but it didn't help, kept it off.