My wife switched to tmo to take advantage of the free data roaming in Japan, and was also told her phone is compatible. She is now in Japan but the data roaming doesn't appear to be working.
What should she see in her system tray to indicate she is connected correctly to free roaming? Which carrier and which band? Currently its says LTE and something like "4000"
Thanks os much for reaching out. LTE won't be likely, but we would expect 2G. Has she tried a manual network selection and looked for Softbank?
I can't find any tech specs online for the Lumia 850. For a phone to work in Japan, it needs to have at least UMTS-2100 (band 1). Japan has no GSM 2G. Many low-end phones sold by T-Mobile (e.g. Galaxy Prime) lack this important international band.
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