addPreSearch and not working in dynamics crm 365 V9

Hi Guys,

I am filter Subgrid records based up on mobilephone number but it is not working. i call the function behind the mobile number field.

this is the code i wrote.

function filterSubgrid(executionContext) {

debugger;
var Sdk = window.Sdk || {};

Sdk.setParentAccountIdFilter = function (executionContext) {

// get the form context
formContext = executionContext.getFormContext();
formContext.getControl("Related_Details").addPreSearch(Sdk.filterCustomerAccounts);
}

Sdk.filterCustomerAccounts = function () {

// Only show accounts with the type 'Preferred Customer'
var customerAccountFilter = "<filter type='and'><condition attribute='new_mobilephone' operator='eq' value='828**********'/></filter>";
formContext.getControl("Related_Details").addCustomFilter(customerAccountFilter, "new_rms");

}

Help Me Guys..

Thank You

Dinesh