Absa refuse to answer questions on their mistakes

Moved bond from Standard Bank to Absa Bank in 2005. 2013 required funds for house alteration amount required greater than present bond. Informed bond was decreased from R1.1m to R****. not told and asked on whos authority. I thought a bond was a binding fixed contract on both sides. According to Absa not so. Told if I want the money take out a second bond. The two bonds would run as one bond except different interest rates. Within the first year make very large payment into the bond account to cover all monthly instalments up to about June 2016. Midway through 2015 telephone calls received stating bond was in arrears. Approached Stellenbosch branch, bonds had been split, all the money was left in second bond. Money was transferred between bonds all went well until January 2016. Letter of demand received with an incorrect amount. Stellenbosch informed their legal department/Debt collector second letter received with a considerably smaller incorrect amount. Another transfer was made. A summons was received. After many telephone calls and e-mails asking questions of Absa legal, [Email Removed] M/S Maria Ramos and meeting with Stellenbosch no answers received fom all of Absa.