always facing importing photos from iPhone 7 to my windows laptop. says device not attached. How to solve?

Old issue... On the phone change the export settings to Keep originals at the bottom of Settings > Photos. The issue is in HEIC > JPEG conversion. If won't help, it could be a second issue with 1080/4k videos. No workaround for this except third-party apps for export. If you won't be able to fix this check iMazing (guide), never had any issues with it.