For a few days my phone was showing all incoming calls forwarded through Google Voice as unknown, this was really confusing as my GVoice is the primary business line. I ran some basic testing and was able to verify that Google Voice was able to normally display the caller ID on other devices and carriers.
This singled it down to either a carrier or software issue, so I factory wiped and put on a different OS.That was a huge waste of time so I began to suspect T-Mobile and called in to get support, they forced me to do 1 hour of tests and blamed me in the end because my phone is rooted. I went to the T-Mobile store and attempted to get a new phone number, they tried to force me to pay $15.
I called customer support and they would not give me the number until they did tests, I explained that I don’t have time to waste troubleshooting problems without getting paid and that I am a customer, not their tech support. The customer service finally relented and gave me a new number for free after saying that they are “99% sure it will not fix the problem”. It fixed the problem 100%.
So how do you fix this problem?
Get a new number from your carrier – it is probably their fault and they will use every excuse to say it is not. If this solved your issue post in the comments so there would be some sort of evidence customers can use to get the service they pay for.