Transfer transaction returns Malformed Request Error

i am trying to run sample [https://gist.github.com/innoprenuer/d4c6798fe5c0581c05a7e676e175e515](https://gist.github.com/innoprenuer/d4c6798fe5c0581c05a7e676e175e515)

The asset creation working fine, however when i transferred asset, it returns
malformed BAD REQUEST
Transaction failed

I am unable to query (via HTTP API) the transaction ID as well, it throws 404 not found error;

**Update:**
It turns out, if i use BigchainDbTransactionBuilder like below,
`Transaction transferTransaction = BigchainDbTransactionBuilder
.init()
.operation(Operations.TRANSFER)
.addInput("FULLFILLMENT", spendFrom, (EdDSAPublicKey) alice.getPublic())
.addOutput("1", (EdDSAPublicKey) robert.getPublic())
.addAssets(aliceRegisterTx.getAsset().getData(), TreeMap.class)
.addMetaData(transferMetadata)
.buildAndSign((EdDSAPublicKey) alice.getPublic(), (EdDSAPrivateKey) alice.getPrivate())
.sendTransaction(handleServerResponse());`

I notice that operation type is not detected, hence making it populated by default (CREATE), however i tried to create a manual version of transaction building (not using builder a.k.a copy paste the code in builder class) the output was set correctly (TRANSFER) but the main problem still linger.

I compared the json output after send transaction, and no invalid structure spotted