I have an HP Spocket that I purchased early in 2018. I just upgraded to an iphone XS Max - and although i reinstalled the app, and my sprocket is fully charged, the phone is not seeing it when I try to set it up.
It initially showed up, but I followed on line instructions and asked it to forget tthe device - now nothing is showing up at all for a sprocket.
If you have tried all possible steps available in this document then its a possible hardware failure and you may call HP Support to obtain a replacement. I've send you a private message with instructions on how to contact your regional HP Support. Could you please check your inbox on the forums page for the private message.
Have a great day!