I think you have to do it old school wifi WPS setup with your router's WPS button --- as the Invoke manual said it has Wifi Protected Setup. Basically you have to pair it with your wifi router, the APP has nothing to do with it.
Go to your wifi router's web setup page. If you still can't pair it, then temporary set up your wifi router with NO password, get your Invoke speaker setup and then turn your wifi password back on.