Listeners Asking to Reset Links
You may receive emails from listeners asking for you to reset their feed link.
You can reset the link by finding the listener in your Listeners & Links area of the feed and clicking "Edit Listener". Flip the switch next to "Subscription Page Available" to turn it blue. Their pages becomes usable again.
(Optional) You can resend the email with that link in case they're having trouble finding it.
After accessing their feed, listeners see "This feed's subscription is already in use. Contact the feed creator to reset your access to the feed." This is to protect their feed from being shared. Resetting the link allows for one more subscription.
It's the same link as the original, it's just "reactivated" so they can access the subscribe buttons again. You don't have to resend it. The listener can just refresh the page and it will work.
Reasons a Listener Will Want Their Link Reset
A listener may have an Android phone as well as an iPad and wants to listen on both devices. Subscribing on the phone prevents the link from being used again on the iPad, so they'll need the link resent to get the iPad subscribed.
Or a listener may accidentally subscribe in an app they didn't mean to, like clicking Apple Podcasts on their computer, but want to listen from Overcast on their iPhone. Or they access the feed by pressing "Copy the RSS Feed" and pasting that link in a browser. This looks no different from an app accessing the feed, which disables their link. If they try again from their phone, the link will not work and they'll need it reset.