# Ho to transfer bnb from opbnb testnet to greenfield testnet?

**URL:** https://forum.bnbchain.org/t/ho-to-transfer-bnb-from-opbnb-testnet-to-greenfield-testnet/3017
**Category:** BNB Greenfield
**Tags:** evm, network
**Created:** [October 14, 2024, 4:02am UTC](https://forum.bnbchain.org/t/ho-to-transfer-bnb-from-opbnb-testnet-to-greenfield-testnet/3017 "2024-10-14T04:02:44Z")
**Posts on this page:** 2
**Page:** 1

<div class="post-metadata">

### Author: ![Sirius](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.bnbchain.org/sirius/32/2015_2.png) [@Sirius](https://forum.bnbchain.org/u/Sirius)
#### Post date: [October 14, 2024, 4:02am UTC](https://forum.bnbchain.org/t/ho-to-transfer-bnb-from-opbnb-testnet-to-greenfield-testnet/3017/1 "2024-10-14T04:02:44Z")

</div>

i write a contract wanting to send some bnb from opbnb to greenfiled testnet.

Here is my code:

```solidity
    function topUpBNB(uint256 transferOutAmount) external payable {
        (uint256 relayFee, uint256 ackRelayFee) = ICrossChain(cross_chain).getRelayFees();
        require(msg.value == transferOutAmount + relayFee + ackRelayFee, "msg.value not enough");
        _topUpBNB(transferOutAmount,relayFee,ackRelayFee);
    }

    function _topUpBNB(uint256 transferOutAmount,uint256 relayFee, uint256 ackRelayFee) internal {
        bool result = ITokenHub(tokenHub).transferOut{ value: transferOutAmount + relayFee + ackRelayFee }(
            address(this),
            transferOutAmount
        );
        require(result,"fail to transfer token");
    }

```

The tokenHub I set is `0x59614C9e9B5Df6dF4dc9e457cc7F3a67D796d3b2`.

And I got the error `execution reverted: the contract and channel have not been registered`

What wrong with it?

I sent bnb from bsc testnet to greenfield successfully before.

---

<div class="post-metadata">

### Author: ![CocoStarZ](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.bnbchain.org/cocostarz/32/1472_2.png) [@CocoStarZ](https://forum.bnbchain.org/u/CocoStarZ)
#### Post date: [October 15, 2024, 2:29am UTC](https://forum.bnbchain.org/t/ho-to-transfer-bnb-from-opbnb-testnet-to-greenfield-testnet/3017/2 "2024-10-15T02:29:39Z")

</div>

no, it’s not supported. pls try transferring from bsc testnet