The "Master Control Unit" or core operating system file (typically the largest file).
You can find the required files on community repositories like Frendx or through archived Google Drive links . nokia c2-01 rm-721 flash file mcu ppm cnt
When you search for nokia c2-01 rm-721 flash file mcu ppm cnt , you are looking for a complete firmware package. Here is exactly what each term means: The "Master Control Unit" or core operating system