It’s there go to my account on t-Mobile app and go to manage data
T-Mobile ONE Plus
$15.00/mo One Plus gives you HD streaming, 20GB of high speed mobile hotspot data, 2X the data speeds abroad compared to T-Mobile ONE in 210+ countries & destinations, unlimited in-flight data on Gogo-enabled flights to, from, or within the U.S., Visual voicemail, and Name ID. On all T-Mobile plans, during congestion, the small fraction of customers using >50GB/mo. may notice reduced speeds until next bill cycle due to data prioritization.