Change of Contract Conditions without Notification

I have been operating my home loan as an access bond for over ten years. The bond was approved as a 108% bond as per point 3 in the special conditions annexure. On the 29th of July some bright spark saw that the bond was at more than 100% and has put a block on the access of the available money. I put my complete pension payout into the bond knowing I could access the amounts I need monthly to live on and now all of a sudden I cannot access my funds. Someone from home loans was supposed to contact me yesterday to sort it out and never did. I find this completely unacceptable and very unprofessional especially for a bank. My bond has never been in arrears and I don't see how any institution can change contractual conditions without discussion with the parties concerned.