diff --git a/cashu/wallet/wallet.py b/cashu/wallet/wallet.py
index c929513c..5558e854 100644
--- a/cashu/wallet/wallet.py
+++ b/cashu/wallet/wallet.py
@@ -834,6 +834,9 @@ def verify_proofs_dleq(self, proofs: List[Proof]):
                 return
             logger.trace("Verifying DLEQ proof.")
             assert proof.id
+            assert (
+                proof.id in self.keysets
+            ), f"Keyset {proof.id} not known, can not verify DLEQ."
             if not b_dhke.carol_verify_dleq(
                 secret_msg=proof.secret,
                 C=PublicKey(bytes.fromhex(proof.C), raw=True),