Contact retailer then solution is like follow

Make backup ( with MT-Nokia for example ) to store Certificates and Sim-Lock data ...
Erase it with Uni-erase...
flash it to any version ( it's best to factory before killing ... )
now phone must power on well but 1234 IMEI and empty SIM lock...
Put in local or Test Mode...
Write now full PM ( all fields ) , readed from good working phone...
Reflash using downgrade instead of Flash button...
Write back certificates.
That's all.