FNB cant provide assistance

New bank client, and I cant pay my credit card due to app issues. Spoke to an agent who couldn't assist so she put me through to the app department who also couldnt explain why I can access eBucks or make payments. Then, when I asked if I could log a complaint, she cut me off. Now, I tried calling in app, and due to technical difficulties, the feature is unavailable and we have to buy airtime to call the other land line to sort this out. Then, I call the help line only to hear SILENCE on the other line as guess what ... technical difficulties and high call volumes. Please explain how I am supposed to wait 3-5 days for resolution as to why I cant make payments ?? Unacceptable. Phone tag for an hour ??? Have I made a mistake changing banks ????