To hard-reset the module and put into pairing mode, hold down the button on the module, it will flash slow – then fast – then go to a solid red, when it goes solid red, take your finger off the button and press it once, then it will begin flashing quickly and you can add it back to the app by selecting “light source wifi” and following the prompts.
This should work to add it to the new network so long as it is 2.4GHz only (not combined with 5GHz) and there is good wifi strength at the install location.
If you have any questions let us know and we can help.