Paid up letter request

I have paid up my Capfin account which was handed over to DMC since the past week I have been trying to call them to request for a paid up letter they are giving me a round around..either their phones are not working or they just hang up and they never respond to any of my emails...their service is poor when they request for payment they even call at night but after they receive them they don’t care about the clients or the importance of a paid up letter