Coolant leak

So after driving my car for 5 hours from PA to NY, the moment I got a block away from my garage the coolant light came on warning of low coolant. After parking the car, I checked underneath for a leak and found nothing, the next day I brought G12+ coolant and added it to the reservoir, in total I added 3L. I turned the car on and ran it for 2 minutes and when I went to check the reservoir it was completely empty again with no leaks coming from the bottom or hose (s) attached to the reservoir. I don’t have a jack to see completely under the car but the ground is free of any signs of a leak. What could possibly be wrong with the coolant system? I also noticed the fan on my engine wasn’t spinning.