If this partition becomes corrupted—usually due to an interrupted firmware flash, improper rooting, or using the wrong "Format All" command in SP Flash Tool—your phone will lose its ability to connect to cellular networks. Common Symptoms of Corrupt NVRAM
You may need a fresh Nokia 2.4 NVRAM file if you notice the following:
Click and connect your powered-off phone while holding the Volume Down button. Method 2: Professional Repair Tools