Worst bank ever

I got offered a 28 month loan one day and then a 12 month loan the next day, I understand the credit information changes but the bank rep told me to come back the next day. After going back the term changed and amount changed which put me in financial distress and was forced to take what they offer. I went into branch to correct this and what I usually do is consolidate my current loan and they give me a longer term which doesn't affect anything negative, but for some reason the bank rep put me to a credit advisor and they did a rescheduling without me knowing full details about it. This affected my credit score and my points dropped by more than 20 credit points in one month. I went to branch and they said there is nothing they can. How is this acceptable? Till today they are saying there is nothing they can do, I spoke to numerous branch managers who offered call backs and still didnt get any, keep in mind this is 5 months ago. I do not know what to do anymore as I was in the process of buying a house right before this started. I need help and need to get this resolved