What is this system icon (looks like upside down Signal strength)?

Does anyone know what the left-most status icon is here? The one that looks like an upside down signal status. It only shows up randomly from time to time, and I've tried toggling on/off different settings (such as night light) to try to make it go away, but nothing has been successful. Rebooting my phone gets rid of it, until the next time it randomly shows up in a few days or weeks. Moto G Power running Android 10, with all current updates.