lenovo a5000 mtk 6582 invaild imei after flash plz help

hello everyone

i have flashed lenovo A5000 with the last fiermware and the iemei got invaild
i have try everything and every method but its keep says metamode failed .

i have all needed drivers CDC MTK preloader but still the same . i have try windows 10 and windows 8 and windows 7 32 bit but nothing … plz i need help with that the phone not mine … its for customer.

sorry for my english .