Go to the bank and open an RRSP account.
You can show them one of the articles.
The bank's back office is BULL SHIT.
You can contribute whatever amount you want. They can not stop you from doing that.
EVEN if you overcontribute and subject to penalties, that's NONE of their business.
Did you have to pay any HK taxes when you withdrew the MPF?
https://www.google.com/search?client=opera&q=how+to+roll+your+MPF+into+RRSP&sourceid=opera&ie=UTF-8&oe=UTF-8