google maps geocoding api

Question

Hi 

i am using google maps  geocoding api with api key to get latitude and longitude from an address , my code is below:

string url = "https://maps.googleapis.com/maps/api/geocode/xml?address=" + area + "," + City + "&sensor=false&Key=xxxxxxxxxxxxxxxxxxxxxxxxxxCvgXy8c"; 

 

but after handling some requests it stops working and return a status code "OVER_QUERY_LIMIT".

does any one have any idea about this problem.