Standard Bank reneging on agreement

I have been banking with Standard Bank for 36 years as a Prestige Member. I also took out a housing loan in 36 years ago linked to an Access Bond facility which I used as needed. In 2016 the bank kindly restructured my loan and reduced my monthly repayment amount.. The condition was that I was not to use my facility for a period of two years. More than two years have since elapsed, but my facility remains blocked. On querying this, I am told that I must now reapply as the faciity lapses if unused for 6 months. I find this totally unacceptable as I was never ever advised by the bank of the facility lapsing. In any event the 2 years condition was imposed by the bank, so I would not have been able to comply with the 6 months stipulation! I now wish to once again use my facility but am being prevented by the bank not adhering to the restructuring agreement terms!!