Software update comes with Bugs & I have to pay???

Hi guys, I'm sorry to do this on your page, but maybe now someone will be willing to help, I just cannot find the Help I need! <br> Immediately after updating to iOS 9 all my apps have gone mad. Every time I switch any app on it automatically switched itself off again..... I have been to the iStore in Cavendish Cape Town twice and I was told its R200 to fix the bugs that apparently come with the new software. Now I feel that this is truly unfair because I did not do anything wrong so why do I need to pay for something that was not my fault. Also the guy at iStore in Cavendish told me to just backup my phone and reset it, did all of that and nothing! My service provider checked too and nothing is wrong on their side, Apple is supposed to be the most secure and safe devices yet I am stuck with bugs on my phone and no one willing to help me. This is not the service I expected from Apple! Especially when safety was the main reason I got your phone. Please Please Help!!!!!