Make sure you have the latest version of the CommBank app installed and repeat the steps above. If you still need help signing up to our service via the CommBank app, you’re best speaking to someone at CommBank. If you’re already a CommBank customer, the easiest way to do this is via the CommBank app. Alternatively, you can call 13 2221. If you’re overseas, you can call 24/7 on +61 2 9999 3283.