Subscription plan cannot be deleted for token(s)

I am trying to delete unneccesarry subscription plans by using Delete Catalog Object API

However I get error 400 saying “Subscription plan cannot be deleted for token(s) sanitized
Object ID is correct
What does this mean and how can I get through? Appreciate your advice.

        "category": "INVALID_REQUEST_ERROR",
        "code": "BAD_REQUEST",
        "detail": "Subscription plan cannot be deleted for token(s) *sanitized*"

:wave: In the current implementation, you cannot delete a subscription plan.
You can optionally disable the existing plan by setting the present_at_all_locations field to false by calling UpsertCatalogObject . For more information, see Disable a subscription plan. When a plan is disabled, existing subscriptions continue to work but you cannot add new subscriptions. :slightly_smiling_face:

thank you for the quick reply.
just wanted to clean up unneccesary list of plans sitting there, but understood they are not able to be deleted.