curl --request PATCH \
  --url https://api.hubapi.com/conversations/v3/custom-channels/{channelId}/channel-account-staging-tokens/{accountToken} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "accountName": "<string>"
}
'

{
  "accountToken": "<string>",
  "createdAt": "2023-11-07T05:31:56Z",
  "genericChannelId": 123,
  "inboxId": 123,
  "userId": 123,
  "accountName": "<string>",
  "deliveryIdentifier": {
    "type": "CHANNEL_SPECIFIC_OPAQUE_ID",
    "value": "<string>"
  }
}