Please insert the SD card properly first. Then unplug and replug the WiFi module. Be sure not to plug the WiFi module reversely, otherwise, it will be burnt. Please plug the WiFi module as below.
Besides, Split starts recording automatically when it is powered up. To enable WiFi, please short press power button to stop recording, and then short press WiFi button to enable WiFi.
If the problem persists, please send a video showing how you operate to email@example.com.