I may sound frustrated, but I am. Here is a summary of my concerns.
1. I use an unlocked OnePlus2 device and a Simple Choice plan that provides free international roaming in certain countries. My wife and both daughters also use a OnePlus device (OnePlus3T, OnePlusX, OnePlus1). Yes, we all are fans of OnePlus devices.
2. We have travelled to India multiple times over last couple of years and had our data roaming working fine soon after landing (and also during transit at other international airports).
3. However, things changed in 2017. My OnePlus data roaming did not work after landing (and in Paris during transit). My family had arrived to India a few weeks before me and they had data available on their phones all the time outside US (even during transit at Abu Dhabi airport).
4. I called T-Mobile support 5 times in less than 24 hours and none could help.
4a. First agent told me that an accidental web block feature was added to my line and she removed it. SHe also mentioned that it takes up to 2 hours for it to take effect and I should wait. I slept a few hours and data was not working after I woke up.
4b. Second agent had me run through various troubleshooting efforts (check data roaming and other settings etc.). She then opened a trouble ticket and said it will take up to 3 days to resolve. I'm travelling for 5 days so most of my trip will be without data outside hotel and office where wifi helped me keep in touch).
4c. Third agent Jen was really good and was able to undestand and troubleshoot technically. She upshed a SIM card update to my phone and said that it was successful and that I should soft reset. She mentioned that she'll be able to check if I'm connected or not and would call me if I'm not connected over data roaming. I waited a couple of hours and received no call.
4d. Fourth agent Brittany was also unable to help and took me through similar troubleshooting steps. She finally declared that it is a non-Tmobile phone and hence I'm not having data romaing available! Even though I used same device on my previous India visit!! She also mentioned that I should buy a device sold by Tmobile. (When my family is connected fine on other OnePlus devices and I was connected previously.)
I then browsed the internet looking for a solution and turned a bit lucky. I found this awesome article written by Michael (http://www.demflyers.com/2016/05/15/how-to-fix-t-mobile-international-data-roaming-on-android/) and these steps helped me achieve data roaming successfully. Kudos to him.
I decided to call T-Mobile again and tell them to update this as a solution in their troubleshooting steps and made another call.
4f. Fifth agent however was not willing to understand the issues with my previous calls and also asked me to buy a T-Mobile device!!! Why was he not willing to listen to my concern? While on the call, he also mentioned to me that previous agent had notated on the account history that she was able to solve my problem and that I was connected. Really? Why would I through pain to search for a solution online if all was working great?
Also, the reason I called was to undestand if any other solution will work better as this may have been a work around to get some data. My family's other phones are connected via default settings and are faster than my phone's data connection while roaming (I understand speeds are slower at 2G levels, but mine is even slower).
I told him that earlier agent had concluded that it is a device issue, but it is not that I'm connected now. He tried to complete the call saying that since data is working now. But, I wanted to get similar roaming speeds as other devices on default roaming settings!
And then the agent thanked me for calling in to Tmobile! He was trying to just cut me off without undestanding my issue of slow roaming data!
T-Mobile, if you are listening, please try to fix this issue for me and people like me. There are so many notes from people facing similar issue and they need to be rewarded being a long-standing loyal T-Mobile customer.