Page 72 of the user guide says this...
To reset some of the menu settings to their original values, select Menu > Settings > Restore factory settings. Enter the security code. The data you have entered or downloaded, such as names and phone
numbers saved in Contacts, are not deleted.
RECEPTION is another matter - the phone needs to be in a place where the signal strength is adequate and that will be more to do with the service provider than to do with the phone.
nds1.nokia.com/phones/files/guides/Nokia_6230i_UG_en.pdf
Good luck...
Peccavi
December 2012
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