iOS laggy/disconnected in WiFi environment

When connected to WiFi with my iphone, the game is super laggy and constantly disconnected to the server. I don’t have this issue with my laptop in the same WiFi environment. And this issue happens for both my iphone 6s and iphone 8. I don’t have this issue when connected to LTE network. I have tried Google’s speedtest tool with my iphone and the download speed is 170Mbps, upload speed is 3.5Mbps.

I have lost lots of games because of this. I can’t find any workaround for this problem. Please share some thoughts to identify the cause even if you are not able to fix this soon.

Not downloading assets could help reducing lag.

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