Share your experience!
I have this phone from a mobile company on a monthly agreement, I got it in September 2015 and from the day I started using it it has turned itself off and rebooted numerous times a day!! It has been back to be 'repaired' 3 times but when they have it it doesn't do it!!! I really need a properly working phone for personal reasons regarding an elderly relative and this one is driving me mad. I have asked for a replacement but they wont do it and since I got it back on 1st February it has done it 127 times to date!! What is wrong with Sony phones????
I'm sorry to hear that, what if you get a brand new SIM card, make sure that you get the correct size (don't cut/trim it) or repair the phone with PCC, have you contacted Sony directly or your carrier/network?
Hi @523,
I'm sorry to hear this. 
It is possible that this can be caused by a faulty SIM card as Uliwooly suspects so see if you can get a new SIM card from your network provider/operator, or test your phone without a SIM for a couple of hours. If you use an SD card I'd suggest that you test your phone without that as well.
Hi,
Try to change network to GSM/WCDMA, M4 aqua doesnt support some 4g networks.
Hope this helps.