diff --git a/README.md b/README.md
index 9ff96c5d..71bbdab3 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
 <img align="right" width="425px" src="https://github.com/xssnick/props/blob/master/logoimg.png?raw=true">
 
 [![Based on TON][ton-svg]][ton]
-![Coverage](https://img.shields.io/badge/Coverage-73.3%25-brightgreen)
+![Coverage](https://img.shields.io/badge/Coverage-73.4%25-brightgreen)
 
 Golang library for interacting with TON blockchain.
 
diff --git a/adnl/rldp/http/client_test.go b/adnl/rldp/http/client_test.go
index 24f4af93..9dd5e40f 100644
--- a/adnl/rldp/http/client_test.go
+++ b/adnl/rldp/http/client_test.go
@@ -440,7 +440,7 @@ func getDNSResolver() *dns.Client {
 	}
 
 	// initialize ton api lite connection wrapper
-	api := ton.NewAPIClient(client)
+	api := ton.NewAPIClient(client).WithRetry()
 
 	// get root dns address from network config
 	root, err := dns.RootContractAddr(api)
diff --git a/liteclient/pool.go b/liteclient/pool.go
index 5d4a0f7f..9cce370a 100644
--- a/liteclient/pool.go
+++ b/liteclient/pool.go
@@ -247,6 +247,11 @@ func (c *ConnectionPool) queryWithBalancer(req *ADNLRequest) (string, error) {
 			return "", ErrNoActiveConnections
 		}
 
+		if reqNode == nil {
+			// no active nodes in list
+			return "", ErrNoActiveConnections
+		}
+
 		host, err := reqNode.queryAdnl(req.QueryID, req.Data)
 		if err != nil {
 			if !errors.Is(err, NetworkErr{}) {
diff --git a/tvm/cell/cell_test.go b/tvm/cell/cell_test.go
index bd77b499..4a8448f7 100644
--- a/tvm/cell/cell_test.go
+++ b/tvm/cell/cell_test.go
@@ -212,6 +212,10 @@ func TestBOCBomb(t *testing.T) {
 	if !bytes.Equal(c.Hash(), hash) {
 		t.Fatal("incorrect hash", hex.EncodeToString(c.Hash()), hex.EncodeToString(hash))
 	}
+
+	if len(c.ToBOCWithFlags(false)) != len(boc) {
+		t.Fatal("len", len(c.ToBOC()), len(boc))
+	}
 }
 
 func TestCell_TxWithMerkleBody(t *testing.T) {
diff --git a/tvm/cell/flattenIndex.go b/tvm/cell/flattenIndex.go
index 9e4ae929..6f3abf27 100644
--- a/tvm/cell/flattenIndex.go
+++ b/tvm/cell/flattenIndex.go
@@ -16,13 +16,18 @@ func flattenIndex(cells []*Cell) ([]*idxItem, map[string]*idxItem) {
 	for len(cells) > 0 {
 		next := make([]*Cell, 0, len(cells)*4)
 		for _, p := range cells {
+			hash := string(p.Hash())
+
+			if _, ok := index[hash]; ok {
+				continue
+			}
+
 			// move cell forward in boc, because behind reference is not allowed
-			index[string(p.Hash())] = &idxItem{
-				index: idx,
+			index[hash] = &idxItem{
 				cell:  p,
+				index: idx,
 			}
 			idx++
-
 			next = append(next, p.refs...)
 		}
 		cells = next
@@ -33,6 +38,26 @@ func flattenIndex(cells []*Cell) ([]*idxItem, map[string]*idxItem) {
 		idxSlice = append(idxSlice, id)
 	}
 
+	for verifyOrder := true; verifyOrder; {
+		verifyOrder = false
+
+		for _, id := range idxSlice {
+			for _, ref := range id.cell.refs {
+				idRef := index[string(ref.Hash())]
+
+				if idRef.index < id.index {
+					// if we found that ref index is behind parent,
+					// move ref index forward
+					idRef.index = idx
+					idx++
+
+					// we changed index, so we need to verify order again
+					verifyOrder = true
+				}
+			}
+		}
+	}
+
 	sort.Slice(idxSlice, func(i, j int) bool {
 		return idxSlice[i].index < idxSlice[j].index
 	})