Can I change feedback that I left?

[lilome.0208]

Hi

I bought a ring. It was stated i. The listing that it was 18ct and the seller assured me that it had been tested as well. When it arrived, it looked good-better than I expected. I keft positive feedback. The next day, though, with a magnufying glass out in the sunlight, I r aluzed that it was hallmafked for 9kt. I started the return process.

Can I change the feedback I  left?

[tobiasd4]

You can't change positive feedback, but you can leaveca follow up comment. 

Does not affect you opening ebay case.