WiFi network stopped working, I need to connect PowerCable MQTT 101x to a different WiFi network. But I do not want to reset the product to factory defaults.

Yes, there are two possible ways to do this:
1) Leave the device powered on and hold the button for 15 seconds until the LED flashes (yellow). The device will re-enter the installation AP mode, where you can connect to its WiFi AP and select another available network from the list.

2) Turn off the PowerCable, use the “NETIO Mobile 2” app to configure new WiFi parameters (SSID + password) over NFC, and then turn the PowerCable back on.