You need to check the following wiki if you are Korean.
https://namu.wiki/w/크레딧코인?from=G-CRE
G-CRE is just an ERC-20 token, so it should be sent to any exchanges using any ethereum wallet.
$CTC is actually ticker of creditcoin, whose mainnet is built on hyperledger sawtooth, so G-CRE should not be $CTC.
But there is no exchange that listed the hyperledger sawooth mainnet coin until now.
So $CTC on any exchanges is just G-CRE, an ERC-20 token on ethereum, not hyperledger sawtooth coin.
Please refer to the following page.
https://namu.wiki/w/크레딧코인?from=G-CRE#toc
If you are still in doubt, contact GOPAX service desk.
https://cs.gopax.co.kr/plugins/servlet/desk/portal/1/create/64