FNB can't fix their own stupid app

FNB is just draining, I opened my account with them and I never got to use that account as their app never worked, it kept on saying temporarily unavailable. That account was close due to inactivity as I couldn't link my number to the app. Yet again I opened another cheque account, still the same thing, I have been to their branches, I have made several calls to their customer care, they keep saying I should give the app 48 hours. I have been doing that and it still does the same. I can not work with cellphone banking as it gives me minimum limits per day. It is really frustrating and it seems like an ongoing issue, like this app thing is out of control, everyone I know has went through the same issue.