Azure B2C Integration with OKTA - issuerAssignedId

Hi OKTA Team ,
I have integrated OKTA with azure B2C. I got stuck at one place where if user is not created in ADB2C , it tries to create user with below identify
“signInType”: “federated”,
“issuer”: “”,
“issuerAssignedId”: “00u4vik1n3JKY5ltq5d7”
I want to skip the SignUp page and want to create the user in AD B2C in advance so that I can skip the SignUp page.
To Create the user in ADB2C , I need issuerAssignedId , I did not found anywhere on how I can get the issuerAssignedId . I checked Access_Token after user logged in OKTA , in claims issuerAssignedId is not present .
Please help me out here.

Thanks in advance!

According to objectIdentity resource type - Microsoft Graph v1.0 | Microsoft Docs this should be the users UUID from Okta.
In the access_token this can be retrieved from the uid claim.

  "cid": "0oa4sx2af0vGkoXb4321",
  "uid": "00u4w1vmhtTY81234567",
  "scp": [

In the id_token this can be retrieved from the sub claim.

  "sub": "00u4w1vmhtTY8Ciuw1d6",
  "name": "Igor Dean",