diff --git a/script/DeployContracts.s.sol b/script/DeployContracts.s.sol
index f18171b..4d32795 100644
--- a/script/DeployContracts.s.sol
+++ b/script/DeployContracts.s.sol
@@ -129,6 +129,7 @@ contract DeployContracts is Script {
         govToken.grantRole(govToken.MINTER_ROLE(), address(votingPowerExchange));
         // give exchange the burner role of utilityToken
         utilityToken.grantRole(utilityToken.BURNER_ROLE(), address(votingPowerExchange));
+        govToken.grantRole(govToken.VOTING_POWER_EXCHANGE_ROLE(), address(votingPowerExchange));
         vm.stopPrank();
 
         return DeploymentResult({
diff --git a/src/VotingPowerExchange.sol b/src/VotingPowerExchange.sol
index 935837c..f2c85e4 100644
--- a/src/VotingPowerExchange.sol
+++ b/src/VotingPowerExchange.sol
@@ -132,7 +132,7 @@ contract VotingPowerExchange is AccessControl, EIP712 {
         }
 
         // burn utilityToken from the `sender`
-        utilityToken.burnByBurner(msg.sender, burningTokenAmount);
+        utilityToken.burnByBurner(sender, burningTokenAmount);
 
         // update the burned amount of the `sender`
         govToken.setBurnedAmountOfUtilToken(sender, currentBurnedAmount + burningTokenAmount);
diff --git a/test/integration/VotingPowerExchange.t.sol b/test/integration/VotingPowerExchange.t.sol
index 171ab34..53ed1cd 100644
--- a/test/integration/VotingPowerExchange.t.sol
+++ b/test/integration/VotingPowerExchange.t.sol
@@ -398,9 +398,15 @@ contract VotingPwoerExchangeTest is Test {
     /////// Exchange tests ///////
     function testExchangeCase1() public {
         bytes32 nonce = bytes32(0);
-        bytes memory signature = helper.generateSignatureFromPrivateKey(dc.DEFAULT_ANVIL_KEY2(), 620 * 1e18, nonce, block.timestamp + 3600);
+        console.log(block.chainid);
+        console.log("Signer address:", vm.addr(dc.DEFAULT_ANVIL_KEY2()));
+        console.log("participant2 address:", participant2);
+
+        bytes memory signature = helper.generateSignatureFromPrivateKey(dc.DEFAULT_ANVIL_KEY2(), 1_000 * 1e18, nonce,  3600, address(votingPowerExchange));
+        address signer = vm.addr(dc.DEFAULT_ANVIL_KEY2());
         vm.startPrank(exchanger);
-        votingPowerExchange.exchange(participant, 100_000 * 1e18, nonce, block.timestamp + 3600, signature);
+        votingPowerExchange.exchange(signer, 1_000 * 1e18, nonce, 3600, signature);
         vm.stopPrank();
+
     }
 }
diff --git a/test/integration/utils/VotingPowerExchangeTestHelper.t.sol b/test/integration/utils/VotingPowerExchangeTestHelper.t.sol
index 967e3e1..73820c4 100644
--- a/test/integration/utils/VotingPowerExchangeTestHelper.t.sol
+++ b/test/integration/utils/VotingPowerExchangeTestHelper.t.sol
@@ -6,17 +6,19 @@ import {DeployContracts, DeploymentResult} from "script/DeployContracts.s.sol";
 import {Test, console} from "forge-std/Test.sol";
 
 import {VotingPowerExchange} from "src/VotingPowerExchange.sol";
+import {MessageHashUtils} from "lib/openzeppelin-contracts/contracts/utils/cryptography/MessageHashUtils.sol";
 
 contract VotingPowerExchangeTestHelper is Test {
     bytes32 private constant _EXCHANGE_TYPEHASH =
         keccak256("Exchange(address sender,uint256 amount,bytes32 nonce,uint256 expiration)");
 
-    function generateSignatureFromPrivateKey(uint256 privateKey, uint256 amount, bytes32 nonce, uint256 expiration)
+    function generateSignatureFromPrivateKey(uint256 privateKey, uint256 amount, bytes32 nonce, uint256 expiration, address exchangeAddr)
         public
         view
         returns (bytes memory)
     {
-        address sender = address(uint160(privateKey));
+        address sender = vm.addr(privateKey);
+        console.log("sender", sender);
         bytes32 structHash = keccak256(abi.encode(_EXCHANGE_TYPEHASH, sender, amount, nonce, expiration));
 
         bytes32 domainSeparator = keccak256(
@@ -25,11 +27,11 @@ contract VotingPowerExchangeTestHelper is Test {
                 keccak256(bytes("VotingPowerExchange")),
                 keccak256(bytes("1")),
                 block.chainid,
-                address(this)
+                exchangeAddr
             )
         );
 
-        bytes32 hash = keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
+        bytes32 hash = MessageHashUtils.toTypedDataHash(domainSeparator, structHash);
 
         (uint8 v, bytes32 r, bytes32 s) = vm.sign(privateKey, hash);