Please, Diamond Bank people, what is the meaning of this?

Just opened a savings account cos I wanted an actual SAVINGS account that wouldnt have any atm card or withdrawal book whatsoever. But the process was annoying (the staff couldnt really answer my questions satisfactorily- like whats ur interest rate etc) and when I didnt tick any box for credit card I was told they would still deduct credit card money anyway - which they did and nobody explained WHY!

But the issue thats really pissing me off is that ever since, Ive been called to Download their app, which when I did go to their app on GoodlePlay people are complaining of all sorts of things in the review Section, besides i dont intend to do any transactions other than depositing money so I really dont need an app. I POLITELY explained these things to the lady but shes relentless in calling and very desperately forcing me to just Download and register- its like she could lose her job or something.... THIS IS WHAT I DONT UNDERSTAND! Why Is Diamond Bank doing this??

I DO NOT WANT THE APP- AND NOBODYS JOB SHOULD BE THREATHENED because OF THAT!!