Hello and Welcome to FixYa!
The solution is simple but needs two things, other than your time and attention :-)
1st) You need the USB data Cable of your phone, if you have it its Good otherwise get it from your friend or someone its called DCU-60, its common in nearly all K and W-series phones.
Ok 2nd) A PC/Laptop with an internet connection.
Have both, please proceed;
and download the Update utility, we are going to update your Phone software, it will clear all the bugs will speed-up your Phones response time and YES! Will bring your phone as in out of the box condition!! All data will be cleared. So back-up before if you want.
Ok, you downloaded the application, install and run it. Its neatly built. You will be guided through the step by step process, it will search for an update if no update is available it will ask you to Update anyway, click yes.
Wait and have a Popcorn pack, and one thing more.. Charge your phone to at-least 60% before flashing, just precaution.
Hopefully you will be happy to see the results, I have had cleared many SE Phones, also many with the Network issue.
If you are still having questions/queries, feel free to ask.
Thank you for using FixYa!, Keep visiting..
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