diff --git a/core/src/ledger/storage_api/collections/lazy_map.rs b/core/src/ledger/storage_api/collections/lazy_map.rs
index 80072f2486..0f60740188 100644
--- a/core/src/ledger/storage_api/collections/lazy_map.rs
+++ b/core/src/ledger/storage_api/collections/lazy_map.rs
@@ -375,9 +375,11 @@ where
         let iter = storage_api::iter_prefix(storage, &self.get_data_prefix())?;
         Ok(iter.map(|key_val_res| {
             let (key, val) = key_val_res?;
+            dbg!(&key, &val);
             let sub_key = LazyCollection::is_valid_sub_key(self, &key)?
                 .ok_or(ReadError::UnexpectedlyEmptyStorageKey)
                 .into_storage_result()?;
+            dbg!(&sub_key);
             Ok((sub_key, val))
         }))
     }
@@ -523,6 +525,7 @@ where
 mod test {
     use super::*;
     use crate::ledger::storage::testing::TestWlStorage;
+    use crate::ledger::storage_api::collections::LazyVec;
 
     #[test]
     fn test_lazy_map_basics() -> storage_api::Result<()> {
@@ -583,4 +586,30 @@ mod test {
 
         Ok(())
     }
+
+    #[test]
+    fn test_nested_map() {
+        let mut storage = TestWlStorage::default();
+
+        let key = storage::Key::parse("testing").unwrap();
+        let nested_map =
+            NestedMap::<u32, NestedMap<String, LazyVec<u32>>>::open(
+                key.clone(),
+            );
+        nested_map
+            .at(&0_u32)
+            .at(&"string1".to_string())
+            .push(&mut storage, 100_u32)
+            .unwrap();
+
+        storage_api::iter_prefix_bytes(&storage, &key)
+            .unwrap()
+            .for_each(|a| {
+                dbg!(a);
+            });
+
+        nested_map.iter(&storage).unwrap().for_each(|a| {
+            dbg!(a);
+        });
+    }
 }
diff --git a/core/src/ledger/storage_api/collections/mod.rs b/core/src/ledger/storage_api/collections/mod.rs
index 688b76bd49..c096979dde 100644
--- a/core/src/ledger/storage_api/collections/mod.rs
+++ b/core/src/ledger/storage_api/collections/mod.rs
@@ -58,7 +58,7 @@ pub trait LazyCollection {
     type SubKeyWithData: Debug;
 
     /// A type of a value in the inner-most collection
-    type Value: BorshDeserialize;
+    type Value: BorshDeserialize + Debug;
 
     /// Create or use an existing vector with the given storage `key`.
     fn open(key: storage::Key) -> Self;
diff --git a/proof_of_stake/src/lib.rs b/proof_of_stake/src/lib.rs
index 23ff3326eb..35738a7556 100644
--- a/proof_of_stake/src/lib.rs
+++ b/proof_of_stake/src/lib.rs
@@ -2737,6 +2737,7 @@ where
 
     validator_slashes_handle(validator).push(storage, slash.clone())?;
     slashes_handle()
+        .get_data_handler()
         .at(&processing_epoch)
         .at(validator)
         .push(storage, slash)?;