weak 3g signal after home button replacement

Hi all,

I just replaced the home button of my Iphone 4, it was a breeze thanks to the ifixit guide. After restarting I noticed the Iphone have a weak 3g signal while full signal under Edge and GSM.

I utilize an European Carrier H3G and it goes only on 3G so I need to gain full signal. It's not a location problem as I experienced it in various places.

Please help me to fix this issue.

Thank You.