Poor service

I have been leasing from this company for more than 7 years with no missed rent. I moved out on the 31st however only received my account statement on the 9th, took the time to recalculate and point out the errors in the statement and sent it to the credit controller assigned to my account as we had met before I handed in my notice to vacate. When I received no response from her on the 10th I took the initiative to call her and she refused to speak to me and told the customer service agent that she was not allowed to speak to me due to reasons he can not disclose to me, she proceeded to reply to my email to say she is escalating it. On Monday 13th at 14:25 she proceeded to send a response that all is in order without engaging the errors I pointed out in my initial email and in the accounts records. I asked for a meeting to point to them that they are debiting the account twice and are not recognizing the interest earned and I was told the person she escalated to has already knocked off. I asked for a call and no feedback was given. Based on the treatment and lack of assistance I am receiving, I would advice a prospective tenant to think twice before dealing with this company, trying to escalate internally never works.