If you are member of more than one subscription, you can choose which subscription you want to work in at any time.
For example, if you are responding to a story, make sure you are responding from the subscription you expect.
To change your active subscription, open the drawer using the green menu icon. Then open the use the drop-down menu near the top of the drawer. It will say your current subscription:
clicking the box will open a list of all the other subscriptions you are on. Select the subscription you want to work in.
If you can't see a drop-down list, then you are currently a member of only one subscription.
To see all your subscriptions, including any which have expired, go to your subscriptions page.