Can A buyer review can be modified or change, in case buyer unable to do by himself?

First buyer has given 1 star rating because of delivery issue. we have served well and buyer is now happy. she had email me that she has changed comment, and star rating also. but she is unable to take screenshots of the same.

now based on this can i request amazon to investigate it? or how to deal in this situation.

below is buyer email:

This original review is no longer on Amazon as far as I can see. I have written one under the name 'Anonymous' which says'Overpriced but my grandson loved it. Then explaining that after receiving a damaged copy you kindly replaced it and I commented, ' full marks for customer service'

But i can not see any changes in the amazon page from my side.

Please guide..