You're looking for a small brown tube that replaced another container that was unfortunately muggled. If you're in the right location, you'll easily see a collection of retail establishments frequented by good folks, making this a muggle-prone location requiring a major dose of stealthiness. Please, respect that fact and take care to subtly remove and replace the container/cache.
Congratulations to Butch724 on FTF honors and to MathSeeker/Woodwalker on following very shortly behind (first container). Bravo all!