2015 and the keys are inside the house.
With the key inside? Late models have a feature that, if you unlock them with the remote and then don't open a door, they'll lock all the doors again after ten seconds. Can you offer more detail? Year? Fresh remote batteries? Keys aren't inside?
Some VW's have a feature to auto lock doors after a set time. I know my GTI does. Scan the manual or Google for automatic locks. Without knowing the exact year i can't help further.
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