Reopen ticket through API

How do I reopen a ticket with status=Closed? It seems to ignore the state on TicketEntity. I would think the following should work, but the status on the ticket remains Closed

        var ticket = await agent.GetTicketEntityAsync(ticketId);
        ticket.BaseStatus = TicketBaseStatus.Active;
        await agent.SaveTicketEntityAsync(ticket);

        var newTicket = await agent.GetTicketEntityAsync(ticketId);
        if(newTicket.BaseStatus != TicketBaseStatus.Active){
            throw new Exception(":exploding_head:");
        }