Prior reading (rather than typing it out again): https://www.geekzone.co.nz/forums.asp?forumid=11&topicid=214830

For the TL;DR version
When I play Pokemon Go with a device called the PoGo Plus (which allows the game to be played with the screen off) via mobile data and with the screen off, I get error messages on the PoGo Plus
When I play Pokemon Go with a device called the PoGo Plus via WiFi, using a mobile data connection obtained on another device with the screen off, the game works fine
When I play Pokemon Go with a device called the PoGo Plus via mobile data and with the screen turned on, the game works fine

When I removed my 2Degrees SIM card and put in a Vodafone Data only SIM, and then when I play Pokemon Go with a device called the PoGo Plus (which allows the game to be played with the screen off) via mobile data and with the screen off, the game worked

Does anyone know how I would get my 2Degrees connection to be as stable as the Vodafone connection is, when playing Pokemon Go in Dunedin CBD (Octagon and surrounding area)?

I really don't want to move over to Vodafone as I would loose my current benefits with 2D and I have no real issues with 2D service - however I guess the Pokemon Go game does

My first thought is a SIM card swap - just in case the one I have is faulty..

Cheers