This looks like a scam : r/humblebundles

5 Humble Bundles Budding Game Developers Can't Miss

Humble Bundle: test & review (read before buying!)

Humble bundle support and refund problem

Humble Bundle: Audio Odyssey -- Tier 1 -- (6 Packs)

Refund policy – nursingbundle

No Man's Sky refunds: Steam says no special exemptions; other sites reportedly offering money back

Humble Bundle will start capping charitable donations again

How to Get a Humble Bundle Refund [98% Success]

Rust lost a huge sum on the player's refund requests

Humble Bundle and Steam Refunds