Why is my iPhone4s not getting any network connection?

Hello Guys,

i bought an i phone 4s last year with R-SIM9 device and i only managed to use it for few months on my country network(Orange Botswana,Africa) then a couple of days after updating the IOS, I removed the sim and from then on it would not connect again to any network and now at the repair store they say i need a new motherboard. please help and thank you..