Call error after ics update to my xperia u

[happyXU]

After updating my xperia u to ics I got an issue. If I put the phone in idle mode means not doing anything at all with it for 2-3 hrs. and after that If I make a call to someone the call progress icon is just circulating but no call is possible. But if I switch it off and then  switch on then it works f9. Don't know what to do. If some fellas have a solution pls help me.

[Johan]

Check if the same problem can be replicated using another SIM card as well. If so, try reinstalling the software using SUS and check if this still remains.

http://www.sonymobile.com/gb/tools/update-service/