Hi @ben160. If all of your software/firmware is fully up to date and this is still happening then it suggests a hardware issue in this case: either with the USB cable or USB port on the phone. I'd advise popping into your nearest Support Centre for them to have a look (if you've not done so already).
You can upload files to the Google Drive easily and then download them onto your Android phone or computer anytime and anywhere you like.Upload photos from Android phone to Google Drive
Step 1. Open Google Drive on your Android phone and then login to your Google account.
Step 2. After entering the service, you need to click on the "+" icon and then choose Upload from the listed options.
Step 3. Now you will see a list of files are displayed on the interface. You can elect Images or Gallery from the list to view the photos on your phone.
Step 4. Next, you can tick the pictures that you want to transfer and tap on Done to start the moving process.
When you connect your Samsung phone to Windows PC with a USB cord, you might see a pop-up of AutoPlay appear on the window, offering several options to deal with your device. You can take full advantage of this AutoPlay feature of Windows PC to transfer photos from Samsung phone to computer easily.
Step 1. Connect Samsung phone to computer.
Step 2. Select "Open folder to view files" on AutoPlay.
Step 3. Sync Samsung photos to computer.