Help with iphone 3gs

[MadChatter]

Ok so i bought an iphone 3gs and when i got it home i restored it to factory settings because i wanted to set it up as a new iphone
But after restore it would not activate so i tried lots of sim cards on lots of networks and still no joy, i put it in recovery mode and tried again with still no joy. I then decided that i could do nothing more so i took it to a phone unlock shop and they managed to get it activated, unlock to any network,and jail break it but its on ios 4.1 and the guy said if i try to update the iphone it will go back to not activating so im stuck with an iphone 3gs that only works like a 3g as no apps or anything will work on 4.1. So my question is can i fix this or is the guy correct?and if its fixable can someone tell me how. I have now paid over £100 with buying iphone and the guy fixing it and now a bit gutted that its useless. thanks

PS, hopefully this post is in the correct section.

EDIT- Right i have managed to get it back on using redsnow and now have cydia installed but cant get Evasi0n to untether as my phone is now updated to 6.1.3 ios. and i also have the no service message on phone so now my phone is an ipod. Can i unlock using ultrasnow? and if i do unlock with ultrasnow how can i boot my phone back up after installing ultrasnow without cydia dissapearing from iphone? (it done this the last time and had to start from scratch) do i just reeboot phone using redsnow just boot? and will i need to do this everytime? thanks

[EVO]

Ok so i bought an iphone 3gs and when i got it home i restored it to factory settings because i wanted to set it up as a new iphone
But after restore it would not activate so i tried lots of sim cards on lots of networks and still no joy, i put it in recovery mode and tried again with still no joy. I then decided that i could do nothing more so i took it to a phone unlock shop and they managed to get it activated, unlock to any network,and jail break it but its on ios 4.1 and the guy said if i try to update the iphone it will go back to not activating so im stuck with an iphone 3gs that only works like a 3g as no apps or anything will work on 4.1. So my question is can i fix this or is the guy correct?and if its fixable can someone tell me how. I have now paid over £100 with buying iphone and the guy fixing it and now a bit gutted that its useless. thanks

PS, hopefully this post is in the correct section.

EDIT- Right i have managed to get it back on using redsnow and now have cydia installed but cant get Evasi0n to untether as my phone is now updated to 6.1.3 ios. and i also have the no service message on phone so now my phone is an ipod. Can i unlock using ultrasnow? and if i do unlock with ultrasnow how can i boot my phone back up after installing ultrasnow without cydia dissapearing from iphone? (it done this the last time and had to start from scratch) do i just reeboot phone using redsnow just boot? and will i need to do this everytime? thanks

if you havent already found the solution to your issue, there is no jailbreak for iOS 6.1.3........yet

i apologize for the response delay