Type *#06# into the phone app. If digits appear, your IMEI is intact, and you likely have a SIM or carrier issue.
Disclaimer: These methods are intended for restoring an original, legal IMEI that was lost due to software corruption. Changing an IMEI to bypass a blacklist is illegal in many jurisdictions. 1. Using Meta Mode Tools (Exynos Chipset) motorola one action imei repair
Widely considered the best for Motorola Exynos repair. It can often perform "Repair IMEI" or "Patch Certificate" functions via a USB cable. Type *#06# into the phone app