Multi-mapping to the same table twice

How do you use Dapper's Multi-Mapping feature on two fields using the same table? i.e ClientInfo has two Address objects.

public class ClientInfo
{
    public Guid Id => Guid.NewGuid();
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public Address PostalAddress { get; set; }
    public Address BillingAddress { get; set; } 
    public int ContactNumber { get; set; }        
}

public class Address
{
    public Guid Id = Guid.NewGuid();
    public string FirstLine { get; set; }
    public string SecondLine { get; set; }
    public string Town { get; set; }
    public string PostCode { get; set; }
}

Tables

Relational - Address.Id used in ClientInfo.PostalAddress / BillingAddress

tbl.Address
|Id|FirstLine|SecondLine|Town|PostCode    

tbl.ClientInfo
|Id|FirstName|LastName|PostalAddress|BillingAddress|etc..

Current implementation

Results only in all but PostalAddress being mapped.

var sql = @"select * from ClientInfo c left join Address as a on a.Id = c.PostalAddress left join Address as ad on ad.Id = c.BillingAddress";

var clients = connection.Query<ClientInfo, Address, Address, ClientInfo>(
                    sql,
                    (client, postal, billing) =>
                    {
                        client.PostalAddress = postal;
                        client.BillingAddress = billing;
                        return client;
                    },
                    splitOn: "PostalAddress,BillingAddress")
                .Distinct()
                .ToList();

return clients;