Arduino MKR NB 1500: direct link

I'm trying to do a TCP connection with direct link. It is connected with the server when I write to the modem AT+USODL=soscket and the modem responses CONNECT. But when I send data to the Arduino, it is not read anything.
The modem is a SARA-R410M-02B with firmware version L0.0.00.00.05.12 [Mar 09 2022 17:00:00]
The code to do the connection is the following:

MODEM.send("AT+USOCR=6"); // With the response I go _socket != MODEM.sendf("AT+USOCO=%d,\"%s\",%d", _socket, _host, _port);
MODEM.sendf("AT+UDCONF=5,%d,100", _socket);
MODEM.sendf("AT+UDCONF=6,%d,2048", _socket);
MODEM.sendf("AT+UDCONF=7,%d,-1", _socket);
MODEM.sendf("AT+USODL=%d", _socket);

There is something missing but I don't know what it is.