Hi @Madaboutpiggies
Welcome to the HP Support Community. I'd be happy to assist you
Due to the current global COVID-19 situation, we're seeing an influx of customers coming in for support. We appreciate your patience.
What is the error you're receiving when you try and enroll in instant ink?
Do you have an image that states free ink?
Please share the image here.
Instant Ink is basically a monthly subscription-based service from HP where you pay a fee each month for the number of pages you print, and HP will deliver new ink cartridges when your printer is about to run low.
Refer to this document to know how to enroll to instant ink Enrolling in HP Instant Ink
Also, read the terms and conditions before enrolling : HP INSTANT INK TERMS OF SERVICE
Hope this helps! Keep me posted.
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