HP’s official support page can be found at https://support.hp.com/. To best work with HP’s website and deal with support, you will need your product name, number or serial number. Detailed instructions on finding your serial number can be found here https://support.hp.com/us-en/document/c04559742 while similar instructions for finding your product number can be found here https://support.hp.com/us-en/document/c03754824.
After entering your serial number on HP’s website, you will be able to start a live chat session with them. They will also provide a toll-free number, usually 1-800-334-5144, that you can call. If your device is out of warranty, you may be required to pay a fee before you can receive phone support.