During a call, you need to switch to the dialpad to enter the selection numbers. Here's how to get to the dialpad:
- While the call is ongoing, place your iPhone away from your ear (if it's on speakerphone this isn't necessary). The screen will light up.
- At the bottom right corner, you'll see a button that likely says "Hide". Tap it. This will reveal the call options.
- Among the icons that appear, look for "Keypad" and tap it. This will bring up the dialpad where you can enter the number selections.
- Now, you can simply tap the number on the dialpad corresponding to the department you want to connect to.
Trying this method should allow your iPhone to register the number selections you make during calls. If you're still having trouble, it's also worth checking if your iPhone software is up to date. Sometimes bugs can be fixed with software updates.