A solution to the problem that has worked for 9to5Mac in testing is to go to Settings, then choose Cellular, then choose your plan, and ensure that “Limit IP Address Tracking” is enabled. Make sure to complete these steps while WiFi is disabled and you are connected to your cellular network. T-Mobile has, however, acknowledged that are situations in which it is required to block iCloud Private Relay due to technical reasons. Namely, if your account or line has content moderation features or parental controls enabled, you will be unable to use iCloud Private Relay when connected to cellular. […] A source has also confirmed to 9to5Mac that this also applies to certain legacy plans that include the Netflix on Us perk and have Family Allowances enabled.
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