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l have an iphone 6 I had bought and used on Tmobile network back in 2015. I keep trying calling Tmobile to have it unlocked but they asked me to use it 40 days on their network. I'm a Tmobile customer for 11 years. There's no way I'll use this vintage phone for 40 days.. I needed it to use abroad for a few weeks installing a local sim card. It was used and paid off years ago. I could not find any person on customer service who could help me. They keep repeating me the same thing that I need to use it 40 days before they can unlock the phone. I already have a better phone I've been using, why would I use an ancient phone for 40 days because of their ridiculous requirement?! I gave up. Now I need to buy a phone somewhere else unlocked this time. Of course I will never ever buy a phone through Tmobile again. Paying off the phone does not make anybody eligible for unlocking an old phone. I called them 8 times but hit deaf ears in India including so called "supervisor".