Hi @leej
Seems as though the recovery partition may have been corrupted as well as the boot partition.
Try using a Win 10 recovery USB and see if that fixes it.
A Win 10 recovery drive can be created from any known working Win 10 computer. All you need is a 8GB USB flashdrive and 40-60 minutes of time.
In the host computer go to Control Panel > Recovery > Create a recovery drive and follow the prompts. To get to Control Panel, type Control Panel in the Windows search box on the desktop and then click on the app that appears.
When you have the USB recovery drive, start the laptop and get into BIOS. You didn’t state the model number so you may have to check how to get into BIOS for your model.
When in BIOS change the Boot order to USB as the first boot option and also enable Legacy USB or CSM (not sure what you will have), save the changes, plug in the USB into the laptop and restart the laptop.
It should boot from the USB drive into the Windows Recovery Environment menus.
Once there go to Troubleshoot > Advanced > Startup repair and follow the prompts. Do not select Reset this PC as this may reinstall Windows and wipe your data