Final answer:
When an improper server is not discovered until after the serve has alternated and the first serve has been contacted, sports like badminton and volleyball typically allow points scored by the improper server to stand and then correct the serving order moving forward.
Step-by-step explanation:
When it is discovered that there has been an improper server after the serve has alternated and the first serve has been contacted, the rules of the specific sport would apply.
In general, sports like badminton or volleyball have specific rules to handle this situation. In badminton, if the error is discovered before the next serve is delivered, the points scored by the improper server are considered valid and the serving order is corrected.
If the game continues and the mistake is discovered later, the scores stand as is and the order is corrected from that point on. Similar rules apply in volleyball, where if an improper server is not discovered until after the game has continued beyond a certain point, generally the points scored remain valid and the error is corrected going forward.