Slow Cellular Data Speed after WiFi is disconnected

I have an iPhone 12 Pro Max and I’m using eSim with AT&T prepaid. Every time I step out of house and disconnects from wifi, I have very sluggish download speed until I restart my phone. Upload speed seems to be be fine though. I’m now on the iOS 15 but I had the same issue even before upgrading to iOS 15. Has anyone experienced the same issue or has found a solution for this issue? Any help is greatly appreciated.

Posted on Sep 30, 2021 4:31 AM

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3 replies

Oct 1, 2021 6:15 AM in response to ribincm

Hello Ribincm,


It sounds like you are experiencing network performance issues when you step outside of your Wi-Fi network. We understand how important this is to you and we are here to help.


We have a very helpful article that you can review. Even though it states no service, this article may still be able to help with your current situation: If you see No Service or Searching on your iPhone or iPad


If the issue persists, can you provide a few more details? What is your download speed as soon as you step out of the house? What is the download speed after restarting your iPhone? Also, does this happen regardless of which Wi-FI network you were connected to?


Cheers!

Oct 1, 2021 8:07 AM in response to SnickZ.

Hello Snickz,


Thank you for your response. When I step out and disconnect from WiFi, I still have cellular connection and my phone shows connected but the download speed is very sluggish, like less than 0.5MBPS. But gets really good speed after I do a restart. I also want to point out that I’m not using a physical SIM card but eSIM built in to the device. Thanks again for your time and please let me know if you need more information.

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Slow Cellular Data Speed after WiFi is disconnected

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