i’m in France, I have this for my bank, Amazon, Paypal and various other shop services etc. I login then, they send an sms with a code which i input and i’m good to go. 99/100……… No biggie.
My telecom provider however gives me a choice - either using a password to login to their servers or using a pin code with a second code sent by their servers to my mobile. I never installed such an app on my iPhone, but obviously they are the provider who knows what they’ve hard wired in ……..
i find this second method intrusive. So for the moment I make sure remember my password.
It’s supposed to increase security…………
BUT, in your case,. I’d probably tell them where to put it and go elsewhere.
J