diff --git a/contracts/interfaces/IUserManager.sol b/contracts/interfaces/IUserManager.sol
index 4ff2810..148314f 100644
--- a/contracts/interfaces/IUserManager.sol
+++ b/contracts/interfaces/IUserManager.sol
@@ -163,11 +163,10 @@ interface IUserManager {
      *  @param account User address
      *  @param token The asset token repaying to
      *  @param lastRepay Last repay block number
-     *  @return Number of frozen stakers, so we know if repay overdue loan works.
      */
     function repayLoanOverdue(
         address account,
         address token,
         uint256 lastRepay
-    ) external returns (uint8);
+    ) external;
 }
diff --git a/contracts/tests/ComptrollerMock.sol b/contracts/tests/ComptrollerMock.sol
index 69bb984..4920411 100644
--- a/contracts/tests/ComptrollerMock.sol
+++ b/contracts/tests/ComptrollerMock.sol
@@ -6,6 +6,7 @@ import "@openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol";
 contract ComptrollerMock {
     address public unionToken;
     uint256 public rewardAmount;
+    uint256 public frozenCounter;
 
     function __ComptrollerMock_init() public {}
 
@@ -38,9 +39,11 @@ contract ComptrollerMock {
     }
 
     function addFrozenCoinAge(
-        address staker,
-        address token,
-        uint256 lockedStake,
-        uint256 lastRepay
-    ) external {}
+        address,
+        address,
+        uint256,
+        uint256
+    ) external {
+        frozenCounter++;
+    }
 }
diff --git a/contracts/tests/UTokenMock.sol b/contracts/tests/UTokenMock.sol
index 09e3a1d..4b5689d 100644
--- a/contracts/tests/UTokenMock.sol
+++ b/contracts/tests/UTokenMock.sol
@@ -40,7 +40,7 @@ contract UTokenMock is ERC20Upgradeable {
         address token,
         uint256 lastRepay
     ) external {
-        frozenCounter = IUserManager(userManager).repayLoanOverdue(account, token, lastRepay);
+        IUserManager(userManager).repayLoanOverdue(account, token, lastRepay);
     }
 
     function updateLockedData(
diff --git a/contracts/tests/UserManagerMock.sol b/contracts/tests/UserManagerMock.sol
index 9153fb6..1c52fed 100644
--- a/contracts/tests/UserManagerMock.sol
+++ b/contracts/tests/UserManagerMock.sol
@@ -144,7 +144,7 @@ contract UserManagerMock {
         address account,
         address token,
         uint256 lastRepay
-    ) external returns (uint8 counter) {}
+    ) external {}
 
     //Only supports sumOfTrust
     function debtWriteOff(address borrower, uint256 amount) public {}
diff --git a/contracts/user/UserManager.sol b/contracts/user/UserManager.sol
index 45c1f16..eee39bd 100644
--- a/contracts/user/UserManager.sol
+++ b/contracts/user/UserManager.sol
@@ -823,13 +823,12 @@ contract UserManager is Controller, IUserManager, ReentrancyGuardUpgradeable {
      *  @param account User address
      *  @param token The asset token repaying to
      *  @param lastRepay Last repay block number
-     *  @return counter Number of frozen stakers, so we know if repay overdue loan works.
      */
     function repayLoanOverdue(
         address account,
         address token,
         uint256 lastRepay
-    ) external override whenNotPaused onlyMarketOrAdmin returns (uint8 counter) {
+    ) external override whenNotPaused onlyMarketOrAdmin {
         address[] memory stakerAddresses = getStakerAddresses(account);
         uint256 addressesLength = stakerAddresses.length;
         for (uint256 i = 0; i < addressesLength; i++) {
@@ -837,7 +836,6 @@ contract UserManager is Controller, IUserManager, ReentrancyGuardUpgradeable {
             (, , uint256 lockedStake) = getStakerAsset(account, staker);
 
             comptroller.addFrozenCoinAge(staker, token, lockedStake, lastRepay);
-            ++counter;
         }
     }
 
diff --git a/test/unit/testUserManager.js b/test/unit/testUserManager.js
index 2228a7c..8a0c4bd 100644
--- a/test/unit/testUserManager.js
+++ b/test/unit/testUserManager.js
@@ -632,10 +632,10 @@ describe("User Manager Contract", () => {
         await uToken.updateLockedData(userManager.address, TOM.address, creditLimit);
         await uToken.updateOverdueInfo(userManager.address, TOM.address, true);
 
-        let count = await uToken.frozenCounter();
+        let count = await comptroller.frozenCounter();
         count.toString().should.eq("0");
         await uToken.repayLoanOverdue(userManager.address, TOM.address, erc20.address, 0);
-        count = await uToken.frozenCounter();
+        count = await comptroller.frozenCounter();
         count.toString().should.eq("3");
     });
 });