Payment not Completed Error in ApplePay.

I am receiving this error Payment not Completed on completeMerchantValidation method, i can confirm that i am receiving an payment session successfully using the link provided from onvalidatemerchant event, Also i am using an verified domain and the phone has test account with test cards. Also i can confirm that the payment is working on applepaydemo website . So my Issue is how to debug this so i can find out what cases my problem. the payment session i am receiving is like the below code:

{
    "epochTimestamp": 1685275564689,
    "expiresAt": 1685279164689,
    "merchantSessionIdentifier": "SSHF****",
    "nonce": "1e95***",
    "merchantIdentifier": "203****",
    "domainName": "same domain i am in and verified" ,
    "displayName": "Z****",
    "signature": "********",
    "operationalAnalyticsIdentifier": "Z***:203****",
    "retries": 0,
    "pspId": "203C****"
}