Start with this article: Click here (please ensure you follow the steps 2, 3, 5 & 6)
Also, try to remove web services and then re-enable web services, most of the time it works.
turn off the web services using this link: Click here - Restart the printer and then, turn in back on using this link: Click here
Here are few important Links - HP Printers - Enrolling in HP Instant Ink - Click here (detailed steps)
Here's another document - please follow step 2 and 3. HP Printers - Setting Up an HP Connected Account: Click here
Step 3: Obtain the printer claim code
Here's a Forums post which seems to have helped others: Click here to check out this related post
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