LinkedIn Sales Navigator login error

I subscribed to LinkedIn Sales navigator through the app store, used it for a while, then cancelled it. After a few days, I chose to subscribe again. I subscribed when logged into my apple account through a browser. When I try to log in to Sales Navigator using my apple ID & password, I keep getting the message: Sorry, this option is unavailable.

Your subscription was purchased via the iTunes store. Please contact Apple to make any changes to your plan.

I contacted LinkedIn Sales Navigator Support and they send me back to Apple. So I'm in a swirl.

What do I need to do in order to access Sales Navigator from a web browser?