Prepare your Controller
Make sure that your controller is reachable from internet over port 8443.
Please identify the external IP of your controller, enable port forwarding if necessary.
Check if you are able to access unifi controller interface by going to https://YOURCONTROLLERIP:8443
If you want to know the IP addresses used by Spotipo cloud check this link.
Configure UniFi Controller Details in Spotipo
On the left tab, select Unifi Controller option.
In the beginning no controller is configured, therefore the status shows "not configured, Click on the settings button.

Select the controller hosted in cloud and click Next.

Enter the host name or IP address of the controller and click Next.

Enter credentials to the controller and click Next.

Select the Unifi site in which you want to enable Spotipo and press Finish.

It can be verified if the controller is connected by going back to the Unifi controller tab, where status 'Online' is shown.
Configure Unifi controller Guest Control Settings
Now log into your Unifi controller and navigate the correct site. Select Guest Control tab and configure the following

Enable Guest Policy
Select Authentication as External Portal server
Under Custom portal, enter IP address as 107.178.247.148
Enable Use Secure Portal
Enable redirect using hostname and enter it's value as logme2wifi.com
Add the following entry to Pre Authorization Access 107.178.247.148/32
Enable Guest Policy on your SSID
Last step is to enable the Guest policy on the SSID
