RIP ma K750

Tried to update the software of ma k750. resulting in total failure of phone. I had already flashed ma phone to w800 .  Absent mindedly i gav a Sony erricson Update for K750. it updated ma phone succesfully. all the process was completed. and my phone wont switch on after tat. tried to giv to a service center. They too say the same. unable to reboot the firmware. now started using a nokia 1100..  😦