Cant read text files after project is built?

I have a tilemap that i need to load in my game, it’s saved in a textfile that the game reads and spawns the tiles by it, it works in the editor and loads it perfectly but when i try to build it and test it there it doesnt find the directory or the file
Here is the code that does the I/O

FString gameDir = FPaths::GameDir();
gameDir += "Content/MapEditor/TestFile";
if (!FPlatformFileManager::Get().GetPlatformFile().DirectoryExists(*gameDir))
{
GEngine->AddOnScreenDebugMessage(-1, 3, FColor::Green, String("Couldnt find directory from path: " + gameDir));
return;
}
gameDir += "\\Testfile" + FString::FromInt(fileID);          
if (!FPlatformFileManager::Get().GetPlatformFile().FileExists(*gameDir))
{
GEngine->AddOnScreenDebugMessage(-1, 3, FColor::Green, FString("Couldnt load the file to a string"));
return;
}