Battery problems
 

I have a 2017 Mini Countryman with 10,000 miles. The last week I had a couple of sluggish starts so I took it to the Mini Dealer who told me I had nine days left on the battery warranty, but they had to run the entire 4-hour diagnostic test before they would cover the battery. Now they're telling me the computer says "User Error" and that I left the lights and drained the battery, and now they won't replace it under warranty. The lights are set on "Auto" and I park in our garage, NEVER even touching the lights switch. Help!