"You might need to upgrade if ITVX is not included in your current Sky package. ITVX is a part of several packages that Sky offers. You can pick the option most closely fits your budget and viewing preferences."
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Troubleshooting ITVX Access Issues
Don’t worry if you’re having trouble using ITVX on Sky. You can take several actions to fix the problem. Check your Sky subscription first, of course. Make sure your package includes ITVX. Consider upgrading your subscription if it isn’t.
Next, check the connections to your Sky box. Ensure your Sky box is turned on and all cables are correctly connected. Try restarting your Sky box if everything appears in order, but there is still a problem.
In case of an emergency, call Sky customer service. They can offer assistance with more complicated problems and solutions to launch ITVX.