function liquidate(address user, uint repaidDebt) public {
    require(repaidDebt > 0, "Must repay positive debt");
    uint debt = debts[user];
    require(getCreditLimitInternal(user) < debt, "User debt is healthy");
    require(repaidDebt <= debt * liquidationFactorBps / 10000, "Exceeded liquidation factor");

    // ****************************************
    uint beforeHealthFactor = getCollateralValue(user) * 1e18 / debt; // @audit remember the health factor before liquidation
    // ****************************************

    uint price = oracle.getPrice(address(collateral), collateralFactorBps); // collateral price in dola
    uint liquidatorReward = repaidDebt * 1 ether / price; // collateral amount
    liquidatorReward += liquidatorReward * liquidationIncentiveBps / 10000;
    debts[user] -= repaidDebt;
    totalDebt -= repaidDebt;

    dbr.onRepay(user, repaidDebt);
    dola.transferFrom(msg.sender, address(this), repaidDebt);
    IEscrow escrow = predictEscrow(user);
    escrow.pay(msg.sender, liquidatorReward);
    if(liquidationFeeBps > 0) {
        uint liquidationFee = repaidDebt * 1 ether / price * liquidationFeeBps / 10000;
        if(escrow.balance() >= liquidationFee) {
            escrow.pay(gov, liquidationFee);
        }
    }

    // ****************************************
    uint afterHealthFactor = getCollateralValue(user) * 1e18 / debts[user]; // @audit health factor after liquidation
    require(afterHealthFactor >= beforeHealthFactor, "Liquidation should not decrease the health factor of the address"); // @audit new check
    // ****************************************

    emit Liquidate(user, msg.sender, repaidDebt, liquidatorReward);
}

function forceReplenish(address user, uint amount) public {
    uint deficit = dbr.deficitOf(user);
    require(deficit > 0, "No DBR deficit");
    require(deficit >= amount, "Amount > deficit");
    uint replenishmentCost = amount * dbr.replenishmentPriceBps() / 10000;
    uint replenisherReward = replenishmentCost * replenishmentIncentiveBps / 10000;
    debts[user] += replenishmentCost;
    uint collateralValue = getCollateralValueInternal(user);

    // ****************************************
    // require(collateralValue >= debts[user], "Exceeded collateral value");
    require(collateralValue >= debts[user] * (1 + liquidationIncentiveBps / 10000 + liquidationFeeBps / 10000), "Debt exceeds safe collateral limit"); // @audit more strict limit
    // ****************************************

    totalDebt += replenishmentCost;
    dbr.onForceReplenish(user, amount);
    dola.transfer(msg.sender, replenisherReward);
    emit ForceReplenish(user, msg.sender, amount, replenishmentCost, replenisherReward);
}
