Momentum refusing to payout or transfer my retirement

In 2018, my previous employer invited a consultant from Momentum to open retirement plan for some of the employees. I had explained to the consultant that I am a foreigner, what will happen when I need my money. He said I will be able to withdraw it without a problem. For the past year, I have been trying to get my money, I can't. I have a trail of emails between momentum and myself including the consultant. I even took a day off to come to the offices in Centurion. I told them I want to transfer my retirement to a different company, i was given a letter. I took it to the company that I want to transfer to, and the company said the letter is not valid. I feel very violated and abused by momentum. I want nothing to do with you. I need my money to be transferred smoothly. Is this how you treat foreigners in South Africa? What a shame!!!! My investment is busy earning interest for you. I need my money paid out asap.