In Subscription Management how do I add new attribute values to the LOV in Manage Event Types?

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In Subscription Management how do I add new attribute values to the LOV in Manage Event Types?

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In Subscription Management how do I add new attribute values to the LOV in Manage Event Types? I'm trying to set up an entitlement plan that covers multiple usage events. I've added new custom fields to the usage event via Apps Composer but I don't know how to add them to my LOV

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