iPad unable to connect T-Mobile wifi

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Recommended settings for Wi-Fi routers and access points - Apple Support

If your iPhone, iPad, or iPod touch won't connect to a Wi-Fi network - Apple Support

Having cleared the basics, perhaps you have iPadOS15 WiFi Private Addressing enabled, this being enabled by default. The WiFi Private Address feature provides additional privacy and security when using “public” (untrusted) WiFi networks. This feature is largely unnecessary for your home WiFi network - and may, in some circumstances, disrupt network connectivity.

This feature is configured for each WiFi network to which you connect. As a diagnostic exercise, try disabling this feature:

Settings > WiFi > [Your Network Name / SSID] - tap the blue “i” icon - Private Wi-Fi Address - set to OFF

More information about this feature can be found here:

Use private Wi-Fi addresses on iPhone, iPad, iPod touch, and Apple Watch - Apple Support

Hello Coreyhend,

We understand that you're running into issues with your iPad not connecting to a specific Wi-Fi network. To research the best option, we need a bit more information. Can you tell us what iPadOS version you currently have installed? This is in Settings > General > About.

Also, have you had a chance to review the article below and try the recommendations it provides? How about restarting your Wi-Fi router/modem?

Recommended settings for Wi-Fi routers and access points - Apple Support

Let us know how that goes, and if you're receiving any error messages when attempting to connect to your Wi-Fi network, and we'll continue researching this issue.

Best regards.