send numeric response on active call

[Android Question]

How do I send a numeric response while on an active call on a T-Mobile LG Optimus F6? The delivery guy shows up at my gated community, calls my cell, then I am supposed to respond (send) a number code to open the gate.

I have had this phone one week.

 

[Rukbat]

Use the dialpad in the phone app.

However, it may not work with a cellphone. You may have to use a wired (landline) phone that the phone company has interconnected to the gate unlock system.