Update a mongo json object

I am trying to update a document but it doesn't update and it doesn't throw any errors.

type Course struct {
	ObjectId    primitive.ObjectID `bson:"_id, omitempty"`
	Id          string             `json:"id"`
	Title       string             `json:"title"`
	Description string             `json:"description"`
	Lessons     string             `json:"lessons"`
	Duration    string             `json:"duration"`
	Details     struct {
		Title             string `json:"title"`
		Instructor        string `json:"instructor"`
		Introduction      string `json:"introduction"`
		Topics            string `json:"topics"`
	} `json:"course_details"`
}

I was not sure if the id was the issue, so I manually entered it as a string, which had no effect.

func (r *CourseRepo) UpdateCourse(ctx context.Context, c *Course) error {
	clog := log.GetLoggerFromContext(ctx)

	objID, err := primitive.ObjectIDFromHex(c.Id)
    if err != nil {
	   return err
    }

   filter := bson.D{
	 {"_id", objID},
   }

	update := bson.D{
		{"$set", bson.D{
			{"title", c.Title},
			{"description", c.Description},
			{"lessons", c.Lessons},
			{"duration", c.Duration},
			{"course_details", c.Details},
		},
		},
	}

	clog.InfoCtx("Filter: %+v", log.Ctx{"filter ": filter})
	clog.InfoCtx("Update: %+v", log.Ctx{"update ": update})

	result, err := r.collection.UpdateByID(ctx, filter, update)
	if err != nil {
		clog.Error(err)

		return err
	}

	clog.InfoCtx("Update Result", log.Ctx{"result ": result})

	return nil
}

logs:

"msg":"Update Result","result ":{"MatchedCount":0,"ModifiedCount":0,"UpsertedCount":0,"UpsertedID":null}}

I have tried UpdateMany / UpdateOne and / UpdateById.

Small snip it of the json I am sending...

   {
        "id": "649411c5d1c770dd462bd181",
        "title": "Algorithms",
        "description": "An awesome course",

Any advice will be greatly appreciated.

I hope I'm not missing anything, but I think you got the IDs mixed up
Try to change the filter to either:

filter := bson.D{
    {"_id", c.ObjectId},
}

or

filter := bson.D{
    {"id", c.Id},
}

*Update
Just recognized you are using UpdateByID() but you pass a filter, try passing objID itself or use UpdateOne() instead like:

    result, err := r.collection.UpdateByID(ctx, objID, update)

or

    result, err := r.collection.UpdateOne(ctx, filter, update)

I am fairly sure if you are passing JSON as

  "_id": "649411c5d1c770dd462bd181"

and this is somehow loaded into the Course struct, then c.Id is ending up a regular string, not a real ObjectId. Later, in your error function, you call

primitive.ObjectIDFromHex(id)

but "649411c5d1c770dd462bd181" is not a valid Go hex string; it needs a 0x or 0X as a prefix (https://www.includehelp.com/golang/hexadecimal-literals.aspx#:~:text=Hexadecimal%20numbers&text=In%20Go%20programming%20language%2C%20a,either%20in%20Uppercase%20or%20Lowercase).

Try prepending 0x e.g.:

    filter := bson.D{
        {"_id", primitive.ObjectIDFromHex('0x' + c.Id)}
    }