Bristol Street Motors Crewe review: Hill start assist part that I am waiting for

I have had my Ford Fiesta for 12 months there is a software problem on it which consists of Hill Start assist that is not working and also Powertrain not working. I was told that it possibly would take some time due to driver shortage etc this I accepted however now Christmas and New Year have finished and have had this part on order for about 5 weeks or more felt the time was right to ask about it I have now sent 2 emails to the Service Manager without any response whatsoever not even an acknowledgement. I then telephoned this morning to be told by someone who was not very helpful in the slightest that he would get Customer Service to ring me this will not happen as it never does. I am paying £239.00 a month for this vehicle and it is not right and nobody tells me what is going on or how long it will be now if this is the way your firm does business then I want no part of it and I want to know what the solution is and would be very grateful if someone could get back to me as a matter of urgency