I've checked our database for any reported issues, and the Standard Bank of South Africa isn't on the list.
With that said, I suggest going through the steps below to resolve this issue:
Open your browser's private window. This disables the cache, which is the usual cause of unexpected browser behaviors.
Google Chrome: Ctrl + Shift + N
Microsoft Edge: Ctrl + Shift + P
Firefox: Ctrl + Shift + P
Safari: Command + Shift + N
If that works, go back to your regular browser and clear its cache.
You can also open an alternative browser available for you. Attempt to connect your online bank from there.
A quick heads up, I've searched for Standard Bank using a test account and found 2 of them. 1 says Standard Bank (South Africa) - Business Banking, which makes the other one for Personal Banking. Please ensure that you connect to the correct online bank account.