When I try to make the second call, either by clicking on a contact, either by entering the number I want, when I click "call" is as if I clicked "back", nothing happens . Only the log is displayed again, without registering the number entered. I finished all running processes imagining that some service may be affecting, but not resolved. I have to restart the device each time you wish to make a connection. This started happening after the last update of the OS. I own a Sony Xperia Z (C6603) running Android 4.2.2 (10.31.A.0.244). Thanks in advance for any help!