Why is Newtonsoft.Json failing to parse a DateTimeOffset value?

I'm using .NET framework and Newtonsoft.JSON package to serialize my object. I have a DateTimeOffset in my object and

{"body":"{ "transactionDate": "2022-02-12T01:22:33+00:00" }"}

causes following error :

Newtonsoft.Json.JsonSerializationException Error converting value 

What is wrong in JSON string format?

public partial class ConsumeWalletRequest
{
    

    [Newtonsoft.Json.JsonProperty("transactionDate", Required = Newtonsoft.Json.Required.Default, NullValueHandling = Newtonsoft.Json.NullValueHandling.Include)]
    public System.DateTimeOffset TransactionDate { get; set; }

}

this class is input parameter of an api

public virtual System.Threading.Tasks.Task<ConsumeWalletResponseApiResultModel> PostConsumeWalletAsync(ConsumeWalletRequest body)
        {
            return PostConsumeWalletAsync(body, System.Threading.CancellationToken.None);
        }

You don't have valid JSON. You have some kind of embedding going on, and it contains quotes around an incorrectly escaped JSON-stringified object.

{"body":"{ "transactionDate": "2022-02-12T01:22:33+00:00" }"}

If you wanted to correctly escape it you would escape the " with \ (this is separate from C# string quoting).

{"body":"{ \"transactionDate\": \"2022-02-12T01:22:33+00:00\" }}

but what you actually want is probably

{"body":{ "transactionDate": "2022-02-12T01:22:33+00:00" }}

See repro here.

I suggest you check how this JSON is generated, because no good JSON parser would create this.