Solidity transfer() 函数得到 0 值

如何解决Solidity transfer() 函数得到 0 值

我有一段可靠的代码，试图将令牌发送到发件人地址。但是，调用函数时发送的值默认为 0。 只有当它被硬编码时，它才会发出真正的值。 这是我的代码

function withdraw() public payable {
    uint256 uid = getID[msg.sender];
    Object.user storage user = details[uid];
    if(user.deficitWithdraw >= 0){
        uint256 amount = user.totalAmount;
        uint256 withdrawalamount = amount;
        uint256 max_withdraw_ = 20000000000;
        if(user.deficitWithdraw.add(withdrawalamount) > max_withdraw_){
            withdrawalamount = max_withdraw_;
            user.deficitWithdraw = user.deficitWithdraw.add(withdrawalamount).sub(max_withdraw_);
        }
        else{
            withdrawalamount = user.deficitWithdraw.add(withdrawalamount);
            user.deficitWithdraw = 0;
        }
        msg.sender.transfer(withdrawalamount);
        // msg.sender.transfer(10000000);
    }
}