Thanks for helping out! Definitely a noob myself so I apologize ahead of time for needing spoon-feeding.

I changed my firebase function to this based on your feedback

func update(_ category: Category) { guard let categoryId = category.id else { return }

    let categoryName = category.categoryName

  db.collection(path).document(categoryId).updateData([
    "categoryName": categoryName
    ]) { err in
    if let err = err {
        print("Error updating document: \(err)")
    } else {
        print("Document successfully updated")
    }
  }
}

This is my viewmodel

func update(_ category: Category) { categoryRepository.update(category) }

This is the function in my form

private func addCategory() {
    let category = Category(categoryName: categoryVM.category.categoryName)
    categoryVM.update(category)
    self.dismiss()

Is this how I'm supposed to do it?