Offline the whole day

We went to FNB branch to replace a signatory in our stokvel. We were told that the system is offline ,we waited from 08h30 until the branch closes by 13h00. As much as I understand that the system will be sometimes offline but how can they be offline from 08h30 to 13h00? It took us 2 months to get all the signatories available on the same day due to other commitments. Now we want you to replace the signatory without us coming to the branch cause we came n u failed us.