Solution:
To change the network for your realme Smart Bulb, you need to remove it from the "realme Link" app and then configure it to the new network. Here's a step-by-step guide:
1. Open the "realme Link" app on your smartphone.
2. Locate the realme Smart Bulb you want to change the network for.
3. Tap on the three dots in the top right corner of the bulb's settings page.
4. You need to remove the device from "realme Link" and configure your device to the new network.