Someone Changed my Mobile App Pin

Yesterday I was on my Mobile App, I had business to do. I logged in from the website and then after logged into my Mobile App to track balances.

This morning I needed to do business on my phone and according to the App my Mobile pin is incorrect. The very same pin I entered yesterday and for years before. How did it change? Most awkwardly??? WHO CHANGED IT??

I want this to be sorted out now. I dont care how you do it! I live 101km away from my nearest branch. So if that means I have to go into the branch to go and change my pin then you will pay me my petrol money to go to Kimberley. I will NOT allow you (your lack of service) to make me put in petrol because you cannot reset my pin via my App.

I await your response