FNB is useless, I am paying for a home but I am declined to take it over

I have a joint bond with my ex husband on two properties that is fianced with FNB, I did an application to take over the bn that I AM CURRENTLY PAYING FOR EVERY MONTH, and I was declined, because I am bieng told that I cannot afford to pay the loan amount every month YET, I HAVE BEEN PAYING FOR IT EVERY MONTH FOR THE PAST 5 YEARS WITH NOT A SINGLE RETURN DEBIT ORDER, HOW IS THIS POSSIBLE, AND ON TOP OF THAT FNB HAS EVEN LOOKED AT THE WRONG PROPERTY THAT I am looking to take over, usless, I am going to approach other banks