c#; webserver; Chinese interpretation is not accurate

After setting up the server according to the document,Parsing Chinese audio, the server returns different results;
Same audio file, C# test and python test,The Python tests are correct.
c# Test results:
`
Result {
"result" : [{
"conf" : 0.277180,
"end" : 4.860000,
"start" : 3.840000,
"word" : "洗洗"
}],
"text" : "洗洗"
}
Result {"text": ""}`

python Test results :
`{
"result" : [{
"conf" : 1.000000,
"end" : 1.260000,
"start" : 0.660000,
"word" : "今天"
}, {
"conf" : 1.000000,
"end" : 1.890000,
"start" : 1.260000,
"word" : "晚上"
}, {
"conf" : 1.000000,
"end" : 2.220000,
"start" : 1.920000,
"word" : "吃"
}, {
"conf" : 1.000000,
"end" : 2.670000,
"start" : 2.220000,
"word" : "什么"
}],
"text" : "今天 晚上 吃 什么"
}
`