Incoming calls

On several occasions I have had an incoming phone call, but have been unable to answer it by pushing the off-cradle icon on the steering wheel.

I am not sure of the exact error message, but it informs my phone is in use (I frequently use the dumbed down Siri feature with that button, and also use the phone to connect to Slacker and iheart radio and its pod casts through the head unit).

Any ideas?

My iPhone is a 5 or 5s.

 

I am going to take this to dealer on Saturday.

Here is the sequence:

1) Phone rings in car indicating an incoming call
2) Display screen immediately reads "Phone call in progress."
3) I push the "off hook" button on the steering wheel -- button on far left of wheel.
4) Phone is not responsive -- does not connect
5) Banner appears over prior screen reading "Mobil Assistant is unavailable when phone is in use."
6) Incoming call in disconnected​

Any ideas?

 

I hate to admit that I was the cause of this, but very happy to let Toyota off the hook.

Turns out I was giving the "off hook button" a long push, rather than a short one.