Unable too login on old mutual app

I signed up with old mutual insure today for household contents. I am able too login on www.ominsure.co.za with my username and password but I am unable to do it on the app. I tried resetting password and username but it says it doesn't recognize my cell number or anything else. When I try too login with my username and password which works fine on the website it gives an error. Policy number:*** ID Number:***

Kindly assist asap.