Thank you for your question, Capfilups! Unfortunately, once the clear protective coating has been damaged, you will not be able to reverse this type of discoloration and you will need to purchase new stopper assemblies. The RP5651RB assembly can be replaced or you can simply replace the flange and stopper, part numbers RP23060RB and RP5648RB.
Best regards, Edward
Date published: 2019-08-07