Access to values just throws exceptions: Not A Map

This is CBOR data that is just arrays of arrays, it's not my data type, it's from a 3rd party. I did not seem to have issue parsing it with python or JS available libs, so I assume I may need to access this in some specific way??
This is effectively the schema of the CBOR encoded data, written in typescript, with WrrRawReqResV1 being the entire encoded object.
export type WrrHeader = [
key: string,
value: Buffer<ArrayBuffer>
]
export type WrrRawRequestV1 = [
requestTimeStamp: number,
requestMethod: string,
requestURL: string,
requestHeaders: WrrHeader[],
isRequestComplete: boolean,
requestBody: Uint8Array
];
export type WrrRawResponseV1 = null | [
responseTimeStamp: number,
responseStatusCode: number,
responseReason: string,
responseHeaders: WrrHeader[],
isResponseComplete: boolean,
responseBody: Uint8Array
];
export type WrrRawReqResV1 = [
format: "WEBREQRES/1",
agent: string,
protocol: string,
request: WrrRawRequestV1,
response: WrrRawResponseV1,
endTimeStamp: number,
optionalData: Record<string, unknown>
];
Access to values just throws exceptions:
Not A MapThis is CBOR data that is just arrays of arrays, it's not my data type, it's from a 3rd party. I did not seem to have issue parsing it with python or JS available libs, so I assume I may need to access this in some specific way??
This is effectively the schema of the CBOR encoded data, written in typescript, with
WrrRawReqResV1being the entire encoded object.