There are several reasons this might be happening:
The transaction hasn't been included in a block. Cryptocurrencies aren't stable, so minor errors sometimes occur. If this happens we will either refund you your money or push the payment through if you can provide the hash (a tx ID) of your transaction.
ETC and ETH confusion. The addresses of Ethereum (ETH) and Ethereum Classic (ETC) have the same structure. If you send ETC or ETH, make sure that you've selected the appropriate transaction type on Changilla. For example, if you create an ETH to BTC transaction, make sure that you send ETH, not ETC. Otherwise your transaction will get stuck.
Wrong or missing XEM message. While sending XEM, make sure that you've put the correct message. It's indicated here and looks like a combination of digits and letters. Messages like 'Hey how are you’, or ‘I love Changilla' are lovely but won’t work, unfortunately.
In case you indicated or forgot to put the valid destination tag for XRP or the valid memo for EOS/Stellar, the transaction won't be processed automatically and you'll have to contact our support team in order for your transaction to be either pushed or refunded manually.