This is the dreaded IMEI corruption issue.

However, (the one printed on the box or under the battery) is generally considered legal maintenance. You are restoring what was lost, not stealing an identity.

Meta Description: Is your OPPO CPH1937 (Realme C2) showing "Invalid IMEI" or "Null IMEI"? Learn the causes, software solutions, and professional repair methods for IMEI corruption on MediaTek-powered OPPO devices. Introduction: The "No Network" Nightmare Imagine this: You pick up your OPPO CPH1937 (widely known as the Realme C2 in many markets) to make an urgent call, only to notice the signal bars have disappeared and are replaced by an "X" or a "No Service" icon. You check the Settings > About Phone, and under IMEI information, you see terrifying words: "Unknown," "Null," or "Invalid."

A: That is a modem firmware or antenna issue. Flash the stock modem.img from the original firmware package using Fastboot.

A: Yes, if you open the device or use SP Flash Tool. However, if the phone is already out of warranty (CPH1937 is a 2019 model), this doesn't matter.

A: No. Maui META works via the bootrom/preloader mode, before Android even loads. Root is irrelevant. Conclusion: You Can Fix the OPPO CPH1937 IMEI The OPPO CPH1937 IMEI repair process is intimidating at first glance, but thanks to MediaTek's developer-friendly architecture, it is one of the easiest phones to restore.

Keywords used: OPPO CPH1937 IMEI repair, fix null IMEI Realme C2, Maui META tool CPH1937, MTK engineer mode IMEI, restore NVRAM OPPO.

Without a backup, you need someone with the same CPH1937 model.