Misinformation and misleading

I'm really frustrated and don't know how will I handle this situation with the festive season already her, I went to Meadowdale branch and took a loan and I told the consultant I will be paying a lump sum into the loan to reduce the installment, the consultant assured me that as soon I pay the lumpsum it will reduce my payments immediately but that never happened, I went to the branch to inquire I was then told we can't do the adjustment now but only after 4 months.......4 months it means my car will be re possessed