FNB all systems down 25/08/17

On Friday 25 August 2017, I had gone to shop where they swiped my card & machine showed insuff funds. Knowing there definately was money in account, I advise the lady to try again. All very embarressing even though you know there is money. Transaction declined again. I then called FNB & was advised that their systems were offline & could not advise when it would be up & running again. It come back up round 12. However, now FNB want to charge me declined service fees, when it was them that were down - that is not right at all!!!