Thanks for joining the community and sorry to hear you are having problems with your Wi-Fi buddy app.
I have just tested it on my device and thankfully I was able to replicate the Error U113. After a few different attempts to replicate it I found that this error only occured when my Mobile Data was switched off.
The Authentication process runs through the mobile network you will need to make sure your mobile data is switched on and your Wi-Fi is switched off for it to correctly Authenticate you.
Please make sure the mobile data is ON and Wi-Fi is OFF and try it again using the auto-connect feature. If you still have the problem after you try this then please let us know and we will see what else we can try.