Lost a business due to incompetence

We went to fnb to apply for a personal loan to buy a business. wee were pre-approved for for the amount needed.We advised the bank we wanted the loan but then got an sms that the loan amount was less,we still wanted to proceed.When money was paid into our account it was way less than what we agreed on.The consultant at fnb said that they accidentally paid our vehicle finance with another bank.fnb said we had to sort it out ourselves as they could do nothing. we paid a deposit for the business and started getting things in order to take over the bussiness. After a month the money was not yet paid back to us and due to this we lost the business. we spoke to branch manager and sales manager at groblersdal branch they did nothing to assist us.we got the money back from mfc but we already lost the business and we lost money already invested in the business. Fnb does not care about their clients and they did not follow procedure and now we are still liable to repay the loan even though we lost the income from the business that was supposed to cover the repayment.