Identify the app before changing anything
An IPTV app cache cleanup is a small maintenance step, but the neighbouring buttons can have very different effects. On your Trex IPTV 8K viewing device, identify the player you actually use and note its version. If a low-storage message appears, read it rather than assuming the subscription is the cause. Keep your legitimate sign-in recovery method available before changing app settings; do not put passwords or private service links in a support screenshot.
Read the two options separately
Amazon places Fire TV app maintenance under Settings, Applications and Manage Installed Applications. Select the relevant player, then read the exact action. Clear Cache targets temporary files. Clear Data is a separate reset of app data and can require setup again. Google makes the same temporary-data versus app-storage distinction in its Android guidance; its phone menus are not Fire TV instructions. Menu wording can vary with software, so stop if the screen does not match.
Check the result once
For a cache-only check, leave Clear Data alone. Reopen the player and allow it to rebuild temporary files; the first opening may take longer. Compare the same short, lawful video before trying another change. Cache cleanup cannot establish why a stream stalls or promise smoother playback. If the warning returns, tell support the Fire TV model, app version, message and action you used. That is more useful than repeatedly clearing everything.