    function testRewardLostAfterTwoPurchases1() public {
        curves.buyCurvesTokenWithName(address(this), 1, "", "");

        address attacker = makeAddr("Attacker");
        vm.deal(attacker, 1 ether);
        vm.startPrank(attacker);
        curves.buyCurvesToken{value: curves.getBuyPriceAfterFee(address(this), 1)}(address(this), 1);
        console2.log(feeRedistributor.getClaimableFees(address(this), attacker));
        curves.buyCurvesToken{value: curves.getBuyPriceAfterFee(address(this), 1)}(address(this), 1);
        console2.log(feeRedistributor.getClaimableFees(address(this), attacker));
    }

    function testRewardLostAfterTwoPurchases2() public {
        curves.buyCurvesTokenWithName(address(this), 1, "", "");

        address attacker = makeAddr("Attacker");
        vm.deal(attacker, 1 ether);
        vm.startPrank(attacker);
        curves.buyCurvesToken{value: curves.getBuyPriceAfterFee(address(this), 1)}(address(this), 1);
        uint256 fee1 = feeRedistributor.getClaimableFees(address(this), attacker);
        console2.log(fee1);
        feeRedistributor.claimFees(address(this));
        curves.buyCurvesToken{value: curves.getBuyPriceAfterFee(address(this), 1)}(address(this), 1);
        console2.log(fee1 + feeRedistributor.getClaimableFees(address(this), attacker));
    }
forge test --match-test testRewardLostAfterTwoPurchases -vvv

[PASS] testRewardLostAfterTwoPurchases1() (gas: 1287980)
Logs:
  3125000000000
  16666666666666

[PASS] testRewardLostAfterTwoPurchases2() (gas: 1303337)
Logs:
  3125000000000
  19791666666666
diff --git a/contracts/FeeSplitter.sol b/contracts/FeeSplitter.sol
index bb24f02..9751902 100644
--- a/contracts/FeeSplitter.sol
+++ b/contracts/FeeSplitter.sol
@@ -66,8 +66,8 @@ contract FeeSplitter is Security {
         if (balance > 0) {
             uint256 owed = (data.cumulativeFeePerToken - data.userFeeOffset[account]) * balance;
             data.unclaimedFees[account] += owed / PRECISION;
-            data.userFeeOffset[account] = data.cumulativeFeePerToken;
         }
+        data.userFeeOffset[account] = data.cumulativeFeePerToken;
     }
 
     function getClaimableFees(address token, address account) public view returns (uint256) {
@@ -94,8 +94,7 @@ contract FeeSplitter is Security {
     }
 
     function onBalanceChange(address token, address account) public onlyManager {
-        TokenData storage data = tokensData[token];
-        data.userFeeOffset[account] = data.cumulativeFeePerToken;
+        updateFeeCredit(token, account);
         if (balanceOf(token, account) > 0) userTokens[account].push(token);
     }
