I am not very sure if JQuery-Ajax will work with Url of Master-Page.
You may try below things.
1) Check you have specified
WebMethod
attribute on your
UpdatePollCount
Method. Someting as below.
[System.Web.Services.WebMethod]
public static string UpdatePollCount(string Data)
{
}
2) I have used "
ICallbackEventHandler" for Ajax call on Matser-Page before. You may have a look at below link for "
ICallbackEventHandler" use. In this Tip/Trick I have shown example of .Aspx page but it also works for Master-Page.
Simplifying Asp.Net Core Ajax