This could be due to log-in or cache. 

First, make sure you're logged in to the App or Web. 

Log-In 

On App, go to "Account" in the bottom right corner to make sure you're logged in. 

On Web (Desktop), go to "Log In" in the upper right corner to get in your account and follow the prompts for access. 

On Web (Mobile), click the upper left corner, then "Log In" 

Clearing Browser Cache

Google Chrome

Click the three dots in the top-right corner.

Go to More Tools > Clear Browsing Data - OR - Delete Browsing Data

Choose a time range (select All Time for a complete clear).

Check Cached Images and Files and click Clear Data.

Mozilla Firefox

Click the menu button (three lines) in the top-right corner.

Select History > Clear Recent History.

Under Details, select Cache, and click OK.

Microsoft Edge

Click the three dots in the top-right corner.

Go to Settings > Privacy, Search, and Services > Clear Browsing Data.

Select Cached Images and Files and click Clear Now.