I went to read a scroll to Rob and got told

Oops! You don't have enough Alchemy Points to activate this spell. Clear some Out

Then clicking the link I got

Robert Pattinson's Learned Spells No Spells Learned! 0/0 alchemy points used

What is your pets intelligence level? For every 16 intelligence you have you'll get 1 alchemy point. You need alchemy points to attach scrolls.

You'll probably find this thread helpful.

Intelligence: 12

But I will check out that link, thank you.