Construct 3 website returning critical errors

Critical error
This should not of happened. Please contact support.

System.ArgumentException: An item with the same key has already been added. at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource) at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add) at System.Linq.Enumerable.ToDictionary[TSource,TKey,TElement](IEnumerable`1 source, Func`2 keySelector, Func`2 elementSelector, IEqualityComparer`1 comparer) at C3.Code.Caching.CityCaching.<>c__DisplayClass1_0.b__0() in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Caching\Cities.cs:line 21 at C3.Code.Controls.Application.Caching.Manager.Manager.Get[T](String key, Func`1 getFromExternFunction, Boolean skipLocalCaches) in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Controls\Application\Caching\Manager\Manager.cs:line 123 at C3.Code.Caching.CityCaching.GetCitiesInCountry(Int16 countryID, Boolean skipLocalCaches) in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Caching\Cities.cs:line 26 at C3.Code.Caching.CityCaching.GetCityID(Int16 countryID, String cityName) in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Caching\Cities.cs:line 35 at C3.Code.Helpers.GeoIP.Functions.GetCityID(Nullable`1 countryID, String cityName) in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Helpers\GeoIP\Functions.cs:line 84 at C3.Code.Helpers.GeoIP.Functions.LookupIP(String ipAddress) in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Helpers\GeoIP\Functions.cs:line 36 at C3.Code.Caching.GeoIPLookupCaching.<>c__DisplayClass0_0.b__0() in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Caching\GeoIPLookup.cs:line 27 at C3.Code.Controls.Application.Caching.Manager.Manager.Get[T](String key, Func`1 getFromExternFunction, Boolean skipLocalCaches) in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Controls\Application\Caching\Manager\Manager.cs:line 123 at C3.Code.Caching.GeoIPLookupCaching.GetIPDetails(String ipAddress) in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Caching\GeoIPLookup.cs:line 21 at C3.Code.Helpers.SEO.Functions.GetUsersIPRegion() in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Code\Helpers\SEO\Regions.cs:line 87 at C3.Pages.Master_Pages.Global.Page_Init(Object sender, EventArgs e) in C:\Dropbox\Dropbox (Scirra Ltd)\Tom\C3 Website\C3Alpha2\Pages\Master Pages\Global.Master.cs:line 48 at System.Web.UI.Control.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)[/code:29uqqkf5]