Paradise is described with أُكُلُهَا دَائِمٌ (13:35)—its provision is abiding. The objection asks how a particular fruit can remain unchanged if it is eaten.
The response distinguishes the enduring supply or kind from the continued numerical identity of every piece. A particular item may be consumed while provision remains constant. Likewise “perishing” does not always mean total nonexistence; it may describe the loss of a particular form or state.