diff --git a/proto/lbm/collection/v1/collection.proto b/proto/lbm/collection/v1/collection.proto
index 96be2977cc..70cf6e0b4a 100644
--- a/proto/lbm/collection/v1/collection.proto
+++ b/proto/lbm/collection/v1/collection.proto
@@ -10,7 +10,7 @@ import "cosmos_proto/cosmos.proto";
 
 // Params defines the parameters for the collection module.
 message Params {
-  reserved 1 to 2;
+  reserved 1 to 2; // depth_limit, width_limit
 }
 
 // Contract defines the information of the contract for the collection.
diff --git a/proto/lbm/collection/v1/genesis.proto b/proto/lbm/collection/v1/genesis.proto
index dab5eb6aa1..658bb633b4 100644
--- a/proto/lbm/collection/v1/genesis.proto
+++ b/proto/lbm/collection/v1/genesis.proto
@@ -32,7 +32,7 @@ message GenesisState {
   // nfts is an array containing the nfts.
   repeated ContractNFTs nfts = 7 [(gogoproto.nullable) = false];
 
-  reserved 8;
+  reserved 8; // parents
 
   // grants defines the grant information.
   repeated ContractGrants grants = 9 [(gogoproto.nullable) = false];
@@ -125,7 +125,7 @@ message NextClassIDs {
   // contract id associated with the contract.
   string contract_id = 1;
 
-  reserved 2;
+  reserved 2; // fungible
 
   // id for the non-fungible tokens.
   string non_fungible = 3 [
diff --git a/x/collection/keeper/migrations/v3/store.go b/x/collection/keeper/migrations/v3/store.go
index 67f60d6c3b..1a51392986 100644
--- a/x/collection/keeper/migrations/v3/store.go
+++ b/x/collection/keeper/migrations/v3/store.go
@@ -39,7 +39,7 @@ func migrateClassStateAndRemoveLegacyState(collectionStore, oldStore storetypes.
 		newClassStore.Set(idKey(id), []byte{})
 		oldStore.Delete(idKey(id))
 
-		detachNFT(collectionStore, cdc, id)
+		detachNFTs(collectionStore, cdc, id)
 		removeFTs(collectionStore, cdc, id)
 	}
 
@@ -57,7 +57,7 @@ func migrateClassStateAndRemoveLegacyState(collectionStore, oldStore storetypes.
 	return nil
 }
 
-func detachNFT(store storetypes.KVStore, cdc codec.BinaryCodec, id string) {
+func detachNFTs(store storetypes.KVStore, cdc codec.BinaryCodec, id string) {
 	iterator := storetypes.KVStorePrefixIterator(store, parentKeyPrefixByContractID(id))
 	defer iterator.Close()
 
@@ -69,7 +69,7 @@ func detachNFT(store storetypes.KVStore, cdc codec.BinaryCodec, id string) {
 
 		var parentID gogotypes.StringValue
 		cdc.MustUnmarshal(iterator.Value(), &parentID)
-		addCoin(store, id, getRootOwner(store, cdc, contractID, tokenID), collection.NewCoin(tokenID, cmath.OneInt()))
+		addCoin(store, id, getRootOwner(store, cdc, contractID, parentID.Value), collection.NewCoin(tokenID, cmath.OneInt()))
 
 		store.Delete(parentKey(contractID, tokenID))
 		store.Delete(childKey(contractID, parentID.Value, tokenID))
@@ -119,7 +119,7 @@ func removeFTBalances(store storetypes.KVStore, contractID, ftID string) {
 	for ; iterator.Valid(); iterator.Next() {
 		id, address, tokenID := splitBalanceKey(iterator.Key())
 		if id != contractID {
-			panic(fmt.Sprintf("v3 migration: inconsistent ContractID, got: %s, expeted: %s", id, contractID))
+			panic(fmt.Sprintf("v3 migration: inconsistent ContractID, got: %s, expected: %s", id, contractID))
 		}
 
 		if tokenID == ftID {