request /construction/submit to submit a signed transaction but return 17 code error who msg is "malformed value"

[tracy139]

there is my demo code:

    TransactionBroadcastRequest request = TransactionBroadcastRequest.builder()
            //encoded by base64
            .signed_transaction(rawTransaction)
            .network_identifier(this.getNetwork(this.chain))
            .build();
    String json = JsonHelper.toJson(request);
    var responseBody = httpClientUtil.postJson(String.format("%s/construction/submit", endpoint), json);

who named as endpoint in the code is a request url prefix, it is rosetta’s mainnet url prefix, and the rawTransaction has been signed my myself.

there is my request body, it is named as “json”:
{“network_identifier”:{“blockchain”:“Oasis”,“network”:“b11b369e0da5bb230b220127f5e7b242d385ef8c6f54906243f30af63c815535”},“signed_transaction”:“MHhhMjczNzU2ZTc0NzI3NTczNzQ2NTY0NWY3MjYxNzc1Zjc2NjE2Yzc1NjU1ODYxYTQ2NTZlNmY2ZTYzNjUwMjY2NmQ2NTc0Njg2ZjY0NzA3Mzc0NjE2YjY5NmU2NzJlNTQ3MjYxNmU3MzY2NjU3MjYzNjY2NTY1YTI2MzY3NjE3MzAyNjY2MTZkNmY3NTZlNzQ0MzAwMDdkMDY0NjI2ZjY0NzlhMjYyNzQ2ZjU1MDAyYTViZTE5ZjIwZTY3OWY3M2ZhMWMyY2Q4MDRmMjM1MDQ5YzEyMzE5NjY2MTZkNmY3NTZlNzQ0NTAwMDVmNWUxMDA2OTczNjk2NzZlNjE3NDc1NzI2NWEyNmE3MDc1NjI2YzY5NjM1ZjZiNjU3OTU4MjAxNWY5NDgwZDJmMjhiZGZkYjllZDdjMTgzNjJlYjdmYTFkZTRhMTA2OTlhYWI4N2YyMGUzOWM0YmM1Y2VmMjAzNjk3MzY5Njc2ZTYxNzQ3NTcyNjU1ODQwNmQ0N2FhMTM5MGQ4NmE3MWQyZmI2ZGNhODhjZjUxYTA0OTk0M2QxMDFmOWY4ZWNkOWM5MjNhY2VjODY1NTQxZDZmYzA5N2M5ZjRkYjk5Y2I1NGVjNzkzYTQ1Zjc3Y2VmODA2OGFlZGQxMWU4N2QxZmU3ZDgyNmY4YTIwZjA4MDQ\u003d”}

it return a error response body
{“code”:17,“message”:“malformed value”,“retriable”:false}

l am looking forward to hear your help, thank you very very much!