Occurs an error 403 when submiting a exit or OCO order

Alpaca Trading Tutorial Requests
1

I have:
A open position with quantity 2 (long position)
A stop order with quantity 1

The error 403 occurs when I submitting a OCO or Exit order with quantity 1 via API
I’m using Alpaca.Markets.3.6.1 in NuGet packages.

  • OCO order:
    {
    “side”: “sell”,
    “symbol”: position symbol,
    “type”: “limit”,
    “qty”: “1”,
    “time_in_force”: “Day”,
    “order_class”: “oco”,
    “take_profit”: {
    “limit_price”: Bid Price of symbol
    },
    “stop_loss”: {
    “stop_price”: price of existing stop order above
    }
    }

  • Exit Order
    {
    “side”: “sell”,
    “symbol”: position symbol,
    “type”: “market”,
    “qty”: “1”,
    “time_in_force”: “day”
    }

NOTE THAT: IT WORKED BEFORE.

Could you please check why we have that error?
It is still working when I submit a exit market order on Alpaca web.