1.检查元交易签名私钥是否正确。 
 
  例如: 
 
  mint元交易:hexPrivateKey私钥是否和to账户对应 
 
  metaTransaction.getSafeMintDigest(to, amount, ddcURI, data, nonce, deadline); 
 
  metaTransaction.generateSignature(hexPrivateKey, digest); 
 
  SafeTransferFrom元交易:hexPrivateKey私钥是否和from账户对应 
 
  metaTransaction.getSafeTransferFromDigest(from, to, ddcId, amount, data, nonce, deadline); 
 
  metaTransaction.generateSignature(hexPrivateKey, digest); 
 
 
 
 
 
  2.检查chainid是否正确,文昌链为1223 
 
  DDC1155MetaTransaction metaTransaction = DDC1155MetaTransaction.builder() 
 
  .setChainId(BigInteger.valueOf(1223)) //文昌链chainid 1223 
 
  .setContractAddress("0x0E762F4D11439B1130D402995328b634cB9c9973") 
 
  .build();