Extremely poor service received - I will not be using this service again.

I have dealt with Momentum on an accident claim and they have referred the car hire to AVIS - initially they will never release the car without a deposit - So the vehicle was returned on the 22nd and then on the 26th I sent a request to find out when I can expect my deposit - Too date I have not received any response so On Friday the 29th I called in and spoke to I think Harriet and she assured me she will get the money released within 48hours - we are now Wednesday - I called now and first call dropped - second call the agent said he will put me to a supervisor and after about 3 min he answered and with any good day etc just said can I help - he then listen to my whole story and then put me on hold to the customer supervisor - waited for another 7 min and then the Customer Supervisor got on and he said he will contact the merchant bank to release the funds- this is extremely poor service and I think Momentum should be made aware for their 3rd Party service - I still am not sure If I will get sorted out as I am typing this whilst I am still waiting on the line with AVIS to resolve my issue -