Surprising Sell Response

Hi Guys, When I put following limit orders via postman to testnet, orders are:
LIMIT BUY:

 {
        "symbol": "BTCUSDT",
        "orderId": 600172,
        "orderListId": -1,
        "clientOrderId": "qC0wOneDY3m2VTYPMhdecV",
        "price": "375.35000000",
        "origQty": "1.00000000",
        "executedQty": "0.00000000",
        "cummulativeQuoteQty": "0.00000000",
        "status": "NEW",
        "timeInForce": "GTC",
        "type": "LIMIT",
        "side": "BUY",
        "stopPrice": "0.00000000",
        "icebergQty": "0.00000000",
        "time": 1596281296509,
        "updateTime": 1596281296509,
        "isWorking": true,
        "origQuoteOrderQty": "0.00000000"
    }

LIMIT SELL:

 {
    "symbol": "BTCUSDT",
    "orderId": 600322,
    "orderListId": -1,
    "clientOrderId": "EzVHWbHarGwee4uZEqq8TP",
    "price": "375.35000000",
    "origQty": "0.10000000",
    "executedQty": "0.10000000",
    "cummulativeQuoteQty": "37.53500000",
    "status": "FILLED",
    "timeInForce": "GTC",
    "type": "LIMIT",
    "side": "SELL",
    "stopPrice": "0.00000000",
    "icebergQty": "0.00000000",
    "time": 1596281973790,
    "updateTime": 1596281973790,
    "isWorking": true,
    "origQuoteOrderQty": "0.00000000"
}

As you see the first buy request is returned with New state and Sell order is return with Filled state. After that, I query the first order(buy) but the state is not changed(Still New state). It must be Partially_Filled. Do I think right?. The other thing which I must add is, before these orders, I hadn’t any open orders. I want to know why sell order is filled? why buy order state wasn’t changed?

If the order is partially filled, the order status will be PARTIALLY_FILLED, please check again.

I think you didn’t get the point. I mean Why the buy request after filling sell request has still New state?

Sorry what I mean is have you query the latest status of this order (orderId = 600172)?
what’s the value of executedQty , if it’s 0, then there is no sell order matched with it.