Hi @SWB08 Have you by any chance moved to Glass from Sky HD or Sky Q? If so all your Marketplace subscriptions are cancelled and you have to re-register (see the following link)
https://www.sky.com/help/articles/sky-marketplace-upgrade
You should be able to re-register as follows:
Go to the bottom of the home page and select the following in this order: MySky / your products / (enter your PIN) / App Subscriptions
Select App subscriptions / Current / and then Discovery + Monthly. Hopefully it will say £0 per month whilst you have a Sky TV subscription. If so select Activate subscription.
Also, see the following link:
https://www.sky.com/help/articles/sky-marketplace-subscribe-to-discovery-plus
If you still can't watch Discovery + try calling Sky for some troubleshooting or contact Discovery who according to other posts on the forum can be very helpful.
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