Financing Issues

It's the 2nd time that we've been pre approved for a home loan but when it comes to completing the application Nedbank has 100's of reasons not to finance 100% homeloans. It's a small amount, yet Nedbank tells us its because of late payments and debit order that bounced. Since we've been banking with Nedbank we've not Once made a late payment and no debit Ord has bounced from our accounts. So where do you get your info from? We receive alerts from Transunion and there's nothing wrong with our credit record. We need this resolved ASAP!