In rare instances, third-party plugins or code snippets may interfere with access to the Subscription List and Subscription Details pages on the My Accounts page. If this occurs, consider adjusting the default permalinks for those pages.
To do this, go to WooCommerce > Settings > Advanced > Subscription Endpoints and change the default endpoints to something else. For example, my-subscription and my-subscriptions.
This will bypass any filter or rule that is interfering with viewing the pages.
Please note that you will need WPSubscription Pro for these settings to work.