I have been doing cloud gaming for a year, on Geforce Now. and I m with Slingshot at home, in Christchurch. the latency ping to the Sydney Geforce Now server is usually at 40ms from christchuch , so Fortnite is still playable on Geforce Now. but suddenly on Thursday last week, the ping shot up to 200ms, and stays at 200ms until today. I reset my router to factory setting, I used my old modem, I tried everything , but nothing works, I tried it on my iPhone 15, and on my MacBook Air 15inch, the ping is very high, cloud gaming unplayable either. a guy on geek zone said to use VPN to route the traffic. so I tried 3 VPN, expressvpn, Surfshark, and Nordvpn. only the Surfshark works, Nordvpn doesnt even connect, and expressvpn connects but the internet is blocked by expressvpn. only Surfshark has good connection to the Geforce now server, and ping is around 42ms, looks good, but Fortnite frame rate is like 30fps, and that gives me huge dizziness, when the Surfshark VPN is active. so those VPN are useless in cloud gaming. 

I suspect that Slingshot routes all the cloud gaming traffic from Auckland to Singapore and then to Sydney server, and that adds another 150ms ping. 

interestingly, all cloud gaming works perfectly fine at my work, which is on Vodafone network, not on Slingshot. geforce now works flawlessly, all VPN works and connects perfectly. no problems at all here, at my work

so, I think the problems lies with Slingshot, so I called them, and talk to a technician, but he couldn't figure out what went wrong...

what can I do now? I will have to switch to another provider. which one is the best ISP then? 

has anyone experienced any of these problems with cloud gaming on Slingshot???

besides , xbox cloud gaming seems to have very high ping as well on Slingshot, not just geforce now. 

normal Fortnite online (not cloud gaming) plays fine,

just the Fortnite cloud gaming on Geforce now has very high ping at 200ms.