I'm about to by a used phone but (Note 10 + 5G) N976N
But it had a custom N975F firmware on it, in order to convert it to dual sim and a modified IMEI
I wanted to restore it to it's original state so I downloaded the latest original firmware from samfw.com and flashed it
After flashing, the modified IMEI is still there and it doesn't recognise sim cards.
How can I restore the original IMEI to fix the sim card read issue?