RejectReason is "MarketClosed"

I’m trying to place an order via API in the demo environment.
This is the response of Tradovate’s API:

HTTP/2 200 OK
X-Permitted-Cross-Domain-Policies: none
Etag: W/“2f1-/MimSH4ASuycqu16NTpdvZUOmeg”
Cross-Origin-Opener-Policy: same-origin
X-Frame-Options: SAMEORIGIN
Content-Length: 753
Origin-Agent-Cluster: ?1
X-Content-Type-Options: nosniff
Cross-Origin-Resource-Policy: same-origin
Date: Tue, 15 Jul 2025 22:35:52 GMT
Strict-Transport-Security: max-age=31536000; includeSubDomains
X-Xss-Protection: 0
Ngrok-Agent-Ips: 79.46.168.84
X-Download-Options: noopen
Referrer-Policy: no-referrer
Content-Type: application/json; charset=utf-8
Vary: Origin
X-Dns-Prefetch-Control: off

{
“success”:true,
“message”:“Segnale ricevuto e processato”,

“executedTrades”:[{

“accountId”:"“,
“accountName”:”
",
“success”:false,
“orderId”:245658880070,
“orderStatus”:“Unknown”,
“tradovateAccountId”:
****,
“executionTime”:“2025-07-15T22:35:52.162Z”,
“environment”:“demo”,
“symbol”:“MNQU5”,
“direction”:“SELL”,
“orderType”:“Market”,
“requestedQuantity”:1,
“executedQuantity”:0,
“fillPrice”:null,
“originalSignalQuantity”:1,
“error”:“Ordine non eseguito - possibile mercato chiuso”,
“errorDetails”:{“rejectReason”:“MarketClosed”,“orderStatus”:“Unknown”}
}
],

“summary”:{
“totalAccounts”:1,
“successful”:0,
“failed”:1
},

“details”:{
“symbol”:“MNQU5”,
“direction”:“SELL”,
“entry”:23009.5,
“stopLoss”:23032,
“takeProfit”:22964.5,
“stopLossPoints”:22.5
}

}

I don’t know what the error is, because I’m sending the order during regular market hours.
Someone can help me?