Newly added security features to online payments can be tricky to handle, especially with some banks. As there are countless different banks, everyone with their own, unique security procedures, we can't give you a step-by-step guide on how to handle those.
However, most of them follow this logic:
You're about to make a purchase in ResQ.
You suddenly see a different view (either by a redirect, pop-up, etc) by your bank.
You need to input your personal ID number, your bank login number, or some other identifier your bank asks for.
You are asked to open your bank's app or the app opens automatically.
You approve the payment with your code / password / fingerprint / face recognition / etc.
You should go back to ResQ app, where things should continue as usual.
If you get stuck at any point, the first thing to do is to return to the other app, either to your bank or to ResQ Club.
If you're still stuck, you might want to close the apps and try again. Your bank is the best option to get help on their own security challenges.