What might cause the StoreKit in-app purchase failure with underlying error: Domain=AMSErrorDomain Code=305 "Purchase Failed" UserInfo={NSLocalizedDescription=Purchase Failed, NSLocalizedFailureReason=Server canceled the purchase}

More than 500 cases in production, I couldn't reproduce it in Sandbox. Full underlying error:

Error Domain=SKErrorDomain
Code=0
"An unknown error occurred"
UserInfo={
    NSLocalizedDescription=An unknown error occurred,
    NSUnderlyingError=0x282db1230 {
        Error Domain=ASDErrorDomain
        Code=504
        "The operation couldn’t be completed. (ASDErrorDomain error 504.)"
        UserInfo={
            NSLocalizedDescription=The operation couldn’t be completed. (ASDErrorDomain error 504.),
            NSUnderlyingError=0x282db0780 {
                Error Domain=AMSErrorDomain
                Code=305
                "Purchase Failed"
                UserInfo={
                    NSLocalizedDescription=Purchase Failed,
                    NSLocalizedFailureReason=Server canceled the purchase
                }
            }
        }
    }
}