Recommended power supply: reliable quality 5V power bank or regulated power supply
Do not use non-compatible power supply solutions that output 9V, 12V or higher voltage to the device. Just because USB-C has the same appearance does not mean that the output voltage is necessarily suitable for this device.
Replace the USB-C cable with a confirmed one that can transmit power.
Replace the power supply with a 5V/1A or higher current capability; "higher current capability" does not mean increasing the voltage.
Disconnect the camera shutter cable and other accessories, leaving only the equatorial mount powered and then test.
If there is still no response, do not disassemble the phone for live testing. Please contact after-sales service and record the power supply model, cable and indicator light status.