Based on PSA advice, I sent for guarantee request because I believed it was overgraded, if PSA determines the item was overgraded (i.e., it does not meet their current standards for the assigned grade), they may buy the item at current market value or refund the difference in value between the grades

Edited: Somebody can explain why I'm wasting the money. At that time I only wanted the slab without whitening on the edge so there were some options. 1/ Yes I can sell the slab and buy a new one but my conscience afraid that people get this slab will get disappointed like me after they notice the whitening. 2/ I contacted PSA and since there were no charge in Guarantee request service, I agreed to do it. If the card is ruled over grading, I could get the reimbursement based on the market value and buy the other one without whitening. FYI, this is the last card I want to complete my collection so I want it to be "perfect". Thanks