MTNZF won't change banking details on shareholders account

I am an MTNZF shareholder. I have been trying to sell my shares but MTN has made it a nightmare as they refuse to change my banking details. I submitted my change of details form on the 14th of November (website says it takes 5 day for details to be changed) yet it's over a month now and my bank details have not been changed meaning I cannot trade. I have been contacting MTN on a regular basis with no assistance the call center agents don't seem to know what they are doing. The only excuse I ever receive is that there is a backlog which is totally unfair, and they don't even seem to be apologetic about it. I just want to sell my shares and not have to deal with MTNZF's poor service. Can MTNZF just give me my money back so we can go our separate ways. ***

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