Inserting data, how?

[rogeralsing]

I'm stuck on the most trivial aspect of just inserting data and I don't find anything in the docs that helps me with this

The calling code:

var span = new Span
{
    timestamp = DateTimeOffset.Now,
    trace_id = "1234567890",
    model = "test"
};
await InsertSpan(connection, span);

The entity:

[PublicAPI]
public class Span
{
    public DateTimeOffset timestamp { get; set; }
    public string trace_id { get; set; }
    public string model { get; set; }
}

The code to insert an entity:

async Task InsertSpan(IDbConnection conn, Span span)
{
    var sqlInsert = 
"""
INSERT
INTO spans (timestamp, trace_id, model) 
VALUES (@timestamp, @trace_id, @model)
""";
    var res = await conn.ExecuteAsync(sqlInsert, span);
    Console.WriteLine(res);
}

It throws with the following exception:

Unhandled exception. ClickHouse.Client.ClickHouseServerException (0x0000003E): Code: 62. DB::Exception: Cannot parse expression of type DateTime64(9) here: @timestamp, @trace_id, @model): While executing ValuesBlockInputFormat. (SYNTAX_ERROR) (version 23.2.1.2537 (official build))

Is it a me problem? is it a library problem? is it a Clickhouse issue?