Executing a CAML query will return this error: "Specified argument was out of the range of valid values. Parameter name: index"

Question

I have the following code inside our console application, to loop through a list of number and query the SharePoint list which is inside a modern communication site:

foreach (var r in allrequests.requests)

{

    Console.WriteLine("Entered foreach ");

    Console.WriteLine("RequestID= "+ r.id);

    CamlQuery camlQuery2 = new CamlQuery();

    Console.WriteLine("CAML initiaited" + r.id);

    r.id = "1";

    camlQuery2.ViewXml = "<View><Query><Where><Eq><FieldRef Name='RiskRequestIDNew'/><Value Type='Text'>" + r.id + "</Value></Eq></Where></Query></View>";

    Console.WriteLine("CAML ViewXML" + r.id);

    ListItemCollection oListItems2 = context.Site.RootWeb.GetList(RisksiteUrl + "Lists/RiskManagement/").GetItems(camlQuery2);

    Console.WriteLine("CAML GetItems" + r.id);

    context.Load(oListItems2);

    Console.WriteLine("Context load" + r.id);

    context.ExecuteQuery();

    Console.WriteLine("execute second CAML");

Now when the code reach context.ExecuteQuery(); it will raise this error:

Specified argument was out of the range of valid values.Parameter name: index