function sell(uint256 _id, uint256 _amount) external {
        (uint256 price, uint256 fee) = getSellPrice(_id, _amount);
        // Split the fee among holder, creator and platform
        _splitFees(_id, fee, shareData[_id].tokensInCirculation);
        // The user also gets the rewards of his own sale (which is not the case for buys)
        uint256 rewardsSinceLastClaim = _getRewardsSinceLastClaim(_id);
        rewardsLastClaimedValue[_id][msg.sender] = shareData[_id].shareHolderRewardsPerTokenScaled;

        shareData[_id].tokenCount -= _amount;
        shareData[_id].tokensInCirculation -= _amount;
        tokensByAddress[_id][msg.sender] -= _amount; // Would underflow if user did not have enough tokens

        // Send the funds to the user
+       uint amt = rewardsSinceLastClaim + price - fee;

-        SafeERC20.safeTransfer(token, msg.sender, rewardsSinceLastClaim + price - fee);

+        if (amt > 0) SafeERC20.safeTransfer(token, msg.sender, amt);
+        else revert("no zero sell.");

        emit SharesSold(_id, msg.sender, _amount, price, fee);
    }
