Generic Save and Load using BinaryFormatter not working

I don't know what I'm doing wrong. Everytime I call method load I get the default(T) which is 0 or null, even if I used the method save before. This is my code for loading and saving

     public static void save<T>(string path, T obj) {
         // Create/Open the file and write the obj
         using (FileStream file = File.Open(Application.persistentDataPath + "/" + path, FileMode.Create)) {
             var bf = new BinaryFormatter();
             bf.Serialize(file, obj);
         }
     }
 
     public static T load<T>(string path) {
         var data = default(T);
 
         // If file exists
         if(File.Exists(Application.persistentDataPath + path)) {
             // Open and read the class data
             using (FileStream file = File.Open(Application.persistentDataPath + "/" + path, FileMode.Open)) {
                 var bf = new BinaryFormatter();
                 data = (T)bf.Deserialize(file);
             }
         }
 
         return data;
     }

If I have tryed to load and save plain ints and objects of this class

  [Serializable]
  public class bundle {
      public int m = 0; 
  }

There are no errors, file is getting created and it's content is this for the object of class bundle

^@^A^@^@^@ÿÿÿÿ^A^@^@^@^@^@^@^@^L^B^@^@^@^OAssembly-CSharp^E^A^@^@^@^Fbundle^A^@^@^@^Am^@^H^B^@^@^@^@^@^@^@^K

So I guess save method is correct.

Thanks in advance!