Pact Pattern Matching

I need some help to write a Pact Regular Expression Pattern Matching test for the below json. I am struggling to write for Account and AdditionalInfo

{
    "Account": [
        {
            "ContractId": "679",
            "Code": "0000",

        }
    ],
    "AdditionalInfo": [
        {
            "Contract`enter code here`Id": "679,
            "errorMessage": "NOT CARRIED OUT"
        }
    ]
}