Can I refund Fortnite Crew if I have duplicate subscriptions?

No. Fortnite Crew subscriptions are non-refundable.

We recommend that you cancel any duplicate subscription(s) to avoid being billed multiple times. Please visit How to check which platform I used to subscribe to Fortnite Crew? for steps on how to identify where you subscribed to Fortnite Crew.
Note: We always recommend subscribing to the Fortnite Crew through the platform you play on the most.