diff --git a/cuckoo_fuzz_test.go b/cuckoo_fuzz_test.go
index 7c6af28..f96bc6e 100644
--- a/cuckoo_fuzz_test.go
+++ b/cuckoo_fuzz_test.go
@@ -75,7 +75,7 @@ func FuzzInsertLookup(f *testing.F) {
 				delete(expected, step.key)
 
 				_, ok = actual.Get(step.key)
-				assert.True(ok)
+				assert.False(ok)
 			} else {
 				_, err := actual.Put(step.key, step.value)
 				assert.NoError(err)