Beyond light recently light gamepass so you may have been accessing it via that. However if you believe you had purchased it separately, you can try restoring your license following the steps listed in the article below. If you continue encountering this issue after you will need to reach out to the platform customer support. https://help.bungie.net/hc/en-us/articles/360049196071-Accessing-and-Restoring-Licenses-to-Destiny-Content