I haven't the foggiest idea why that happened but I do know that you appear to be seeking to import the pictures the hard way. I'd never advise connecting a camera to a laptop. That usually requires either special software or, at the very minimum, the laptop to recognise the camera as an external drive. (Both can lead to difficulties and/or to slow transfers).
Remove the SD card from the camera and insert it into your laptop's card reader. Then you can simply drag-&-drop (or copy-&-paste) the files using Windows Explorer.
If your laptop hasn't got a card reader built into it simply use a USB one. They're not expensive; I've had ones from pound shops that have worked perfectly and there are loads on Amazon, eBay, etc,. e.g.
Amazon.co.uk User Recommendation