Whenever the Hard Disk Short/Long DST test fails that indicates that the Hard Disk Drive has failed and that requires a replacement to resolve the issue
HP will provide a replacement Hard Disk Drive if the Notebook warranty is Active, If not you need buy a SATA Hard Disk Drive from a retail shop nearby
Please Contact HP if your HP Notebook is under warranty, HP would replace the Hard Disk Drive and provide you a Recovery media to restore factory operating system after replacement (if you've not yet created Recovery Discs/USB Media)
Note: Back up all the personal data to an external drive if it's possible. Otherwise you could connect the failed HDD via SATA to USB adapter with another PC or same PC after replacement of HDD & re-installation of OS and try copying /recovering the files. You can also refer to the below shown link for further support
It means that the hard drive is failing and should be replaced as soon as possible, You should back up all your personal data and replace with 2.5" sata drive. I PC is still under warranty get in contact with HP. You will need to reinstall windows 10 on the new drive which can be done with HP recovery disks or by downloading the media creation tool from Microsoft and creating a bootable drive with Windows 10. It will be automatically activated once installed (make sure to install the same edition.