Time Frame inaccurate

I recently app**** for an increase on my credit card. Last week I called the call centre and was approved online, they advised me to go to the nearest branch and take the next steps, which was done on Saturday with all the necessary documents (25.4.15 - Zevenwacht Mall). After completing everything I was told they just need to call my employer on Tuesday to confirm employment and after that everything will be sorted out. Come Tuesday no one called, I called back late Tuesday to find out whats happening and was told it will be sorted out in 12-24 hours starting from Tuesday. Yesterday I complained on FB, got a call and another call....as it turns out the wanted another document BET NEVER CALLED ME INFORM ME THIS IS WHAT THEY STILL NEEDED. I mailed it yesterday yet I am told to WAIT ANOTHER 12-48 hours. This is extremely inappropriate to change the time frame constantly and not feedback from AB side as I am mainly the one contacting them 90% of the time. I am really upset because I am a loyal client and have been paying my account regularly on time.