How to bind a city session to a component in Bitrix?

Question

1C-Bitrix

There is a geolocation module with auto-detection of the city, there is a second component that takes information from the infoblock data with cities, how to insert it so that it substitutes the city session, and if the city is not found or this city does not exist, then substitute another:
Session with the city:
$_SESSION["USER_GEO_POSITION"]["city"]
Component output from the infoblock:

CModule::IncludeModule('iblock');
$arSelect = Array(
    "ID",
    "IBLOCK_ID",
    "NAME",
    "DATE_ACTIVE_FROM",
    "PROPERTY_*"
);
$arFilter = Array(
    "IBLOCK_ID" => 9,
    "ACTIVE" => "Y",
    "NAME" => ""
 );