diff --git a/common/utils/util.go b/common/utils/util.go
index 202d7801..faef363c 100644
--- a/common/utils/util.go
+++ b/common/utils/util.go
@@ -7,6 +7,7 @@ import (
 )
 
 func GenerateMockUserOperation() *model.UserOperationItem {
+	//TODO use config
 	return &model.UserOperationItem{
 		Sender:               "0x4A2FD3215420376DA4eD32853C19E4755deeC4D1",
 		Nonce:                "1",
diff --git a/service/chain_service/chain_config.go b/service/chain_service/chain_config.go
index e686b131..3ce2b73d 100644
--- a/service/chain_service/chain_config.go
+++ b/service/chain_service/chain_config.go
@@ -5,15 +5,16 @@ import (
 	"github.com/ethereum/go-ethereum/ethclient"
 )
 
-var NetworkInfoMap map[types.NetWork]types.NetworkInfo
-var NetWorkClientMap map[types.NetWork]ethclient.Client
+var NetworkInfoMap map[types.NetWork]*types.NetworkInfo
+var NetWorkClientMap map[types.NetWork]*ethclient.Client
 
 func init() {
 	ConfigInit()
 	ClientInit()
 }
 func ConfigInit() {
-	NetworkInfoMap = map[types.NetWork]types.NetworkInfo{
+	//TODO api key secret store
+	NetworkInfoMap = map[types.NetWork]*types.NetworkInfo{
 		types.Ethereum: {
 			Name:   "ethereum",
 			RpcUrl: "https://eth-mainnet.g.alchemy.com/v2/bIZQS43-rJMgv2_SiHqfVvXa-Z1UGoGt",
@@ -26,13 +27,13 @@ func ConfigInit() {
 }
 
 func ClientInit() {
-	NetWorkClientMap = make(map[types.NetWork]ethclient.Client)
+	NetWorkClientMap = make(map[types.NetWork]*ethclient.Client)
 	for chain, networkInfo := range NetworkInfoMap {
 		client, err := ethclient.Dial(networkInfo.RpcUrl)
 		if err != nil {
 			panic(err)
 		}
-		NetWorkClientMap[chain] = *client
+		NetWorkClientMap[chain] = client
 		continue
 	}
 }