For iOS Users
1. Open the JustFit app and go to the "Profile" page.
2. Tap the "Settings" button in the upper right corner of the page.
3. Scroll down to find the "Clear Cache" button and tap it to clear the app cache.
4. After the cache is cleared, try downloading the courses again.
For Android Users
1. Open system settings, go to Apps, App Management, or Apps.
2. Find the JustFit app and tap to enter the app details page.
3. Select "Storage" or "Storage & Cache".
4. Tap "Clear Cache".
5. After the cache is cleared, try downloading the courses again.