[potatoz]

Do you get anything in error logs (addons/sourcemod/logs) from the time when you try to download the map? Are you using FastDL and have it properly set up to your server? Do you get any errors in your CS:GO client console whilst trying to download the map?

You'd need to provide a little more information to get proper help, i'm not the best in this area but at least try to answer the questions above in order for others to help you more easily