Undo button not function after upgrade to 3.1 version

[Fadli]

Hi,

why i can't used my undo button for my xperia ZR after i upgrade to OS 3.1 version. How to solve the issue or to downgrade the version back.

regard.

[_alexdon_]

There is no 3.1 version in Android for ZR.Probably you are talking about 4.3,right?

[Fadli]

yes correct 4.3 version

[_alexdon_]

And what undo button are you talking about?

[Fadli]

The back button

[_alexdon_]

It does not work or appear at all?have you tried forced restart(power button and vol up until the phone vibrates)

[Fadli]

Hi. Tq for your reply.

It icon appear but not function. u means same like if we want to screenshot the phone right. but we need to press vol up button. I already tried but the phone cannnot restart. Its another ways to force restart the phone?

[_alexdon_]

Does it have a red button if you remove back cover?if not,just take off the battery.

[Fadli]

i don't see any red button if i remove the back cover. but i already try to take off the battery and on the phone but still not working. For your information i already set the phone into factory setting but also failed to fix the issue.

[_alexdon_]

Did you use sony update service or pc companion to repair?if yes and not working,take it into service.