C# public class AccountMutations
{
    public async Task<AddAccountPayload> AddAccountAsync(
        AddAccountInput input,
        [Service] DataContext context)
    {
        var account = new Account
        {

            FirstName = input.FirstName,
            SecondName = input.SecondName,
            UserId = input.UserId
        };

        context.Accounts.Add(account);
        await context.SaveChangesAsync();
        return new AddAccountPayload(account);
    }
}

C# public class AccountMutations
{
    public async Task<AddAccountPayload> AddAccountAsync(
        AddAccountInput input,
        [Service] DataContext context)
    {
        var account = new Account
        {

            FirstName = input.FirstName,
            SecondName = input.SecondName,
            UserId = input.UserId
        };

        context.Accounts.Add(account);
        await context.SaveChangesAsync();
        return new AddAccountPayload(account);
    }
}