ConsiderChangingTo.md

function increaseLock(uint256 _depositId, address _receiver, uint256 _increaseAmount) external {
        // Check if actually increasing
        if (_increaseAmount == 0) {
            revert ZeroAmountError();
        }
        // Makes sure the msg.sender is the owner of the lock.
        require(_msgSender() == _receiver, "Not the owner of the lock");
        
        Deposit memory userDeposit = depositsOf[_msgSender()][_depositId];

        // Only can extend if it has not expired
        if (block.timestamp >= userDeposit.end) {
            revert DepositExpiredError();
        }

        depositToken.safeTransferFrom(_msgSender(), address(this), _increaseAmount);

        // Multiplier should be acording the remaining time to the deposit to end
        uint256 remainingDuration = uint256(userDeposit.end - block.timestamp);

        uint256 mintAmount = _increaseAmount * getMultiplier(remainingDuration) / 1e18;

        depositsOf[_receiver][_depositId].amount += _increaseAmount;
        depositsOf[_receiver][_depositId].shareAmount += mintAmount;

        _mint(_receiver, mintAmount);
        emit LockIncreased(_depositId, _receiver, _msgSender(), _increaseAmount);
    }