FNB is useless they should close they doors

FNB is the worst bank ever I have a loan I stopped making payments due to work issues then I tried to get hold of someone to make payments but nobody was willing to help so I left it 3 years past fnb phones me wanting my banking details without doing a security check I refused couse I don't know if it's really fnb so I asked them to send me the account number but nothing thus happened 3 times today I spent 200rand airtime useless people in the mean while the interest is going up if fnb don't want my money they must clear my debt couse they are a total waste of time