iPhone 4S on ios 7.0.3 Carrier Signal Issues

Hi,

I have my iphone 4s for almost 2 years now, bought it in England and I'm currently using it here in the Philippines. It has been network unlocked since I'm now able to use with a Philippine SIM card in which I used 3 Mobile back in England with this phone.

It has been working great until a few days ago. I recently updated the ios to 7.0.3 OTA from 7.0.2. It was succesfully updated, however when my phone battery got empty I recharged it a day after since I left the USB cable charger back at the office. When it was charged already, the concern started. Carrier signal status is always on "Searching" then after that "No Service". I tried all these TS below but nothing works.

1. Changing the Carrier settings from Automatic to Manual.

Detected Carriers like (Globe, SUN and Smart), choosed correct carrier, still nothing.

2. Re-insert SIM Card.

3. Use another SIM Card.

4. Restart phone.

5. Reset Network Settings.

6. Reset to Factory Settings.

7. Restore to Factory Settings using iTunes.

8. Manual update of ios 7.03 using downloaded IPSW from iTunes.

9. Disabled 3G

Next option will go to local Apple iStore reseller.

Need your help badly, if anyone else experienced this situation.

Thanks.