Are you referring to Tmobile in Germany or US. Because the only 5G band in the US the phone can use is N41, which is utilized by Sprint. Now T-mobile has purchased Sprint and is in the process of converting that spectrum so that it can be utilized by T-mobile GSM customers. Until that is rolled out and if the additional spectrum is reused as N41, you will not be able to access 5G in the US. Although you will be able to use bands, 2, 4, 5, 12 for T-mobile 4G LTE connectivity.