Blue Penguin Classics paperback with lighthouse doodle

I lost my blue Penguin Classics paperback yesterday around 3pm near the Grainger Market on Grainger Street in Newcastle. It's a 350-page softcover, about A5 size, with a creased spine and a faint coffee stain on the back cover. Inside, there’s a small lighthouse doodle on page 112 and a yellow sticky note tucked in with my sister's number in my handwriting. The book has sentimental value—it's a gift from my grandmother and I really need it back.