Can I remove Carrier Lock on a fully paid iPhone

rules are rules..you can toss it into your drawer for 40 days while being thankful youre not with Verizon and their 50+ day wait.

it must be active on the account for 40 days..not many out there that get a phone just to toss it into a drawer as a back up either..which is where this issue of yours started. the poster you quoted even has a link that says this. not a whole lot you can do in small claims seeing as how this is mentioned in their fine print. all carriers have a certain amount of days a phone must be active on the account before it can be unlocked. active being the chosen word of the day here..

for giggles…

Unlock eligibility for mobile devices on Postpaid plans

• The device must have been active on the T‑Mobile network for at least 40 days on the requesting line.
• If the device was financed or leased through T‑Mobile then all payments must be satisfied and the device must be paid in full.
• If the device is associated with a canceled account, then the account balance must be zero.
• T‑Mobile may request proof of purchase or additional information in its discretion and certain other exceptions may apply.

Unlock eligibility for mobile devices on Prepaid plans

• At least  365 days  must have passed since the device was activated on the T Mobile network.
• If the device was activated less than 365 days ago, then the   Prepaid account associated with the device must have had more than $100 in refills during that period for each line active on the account.  In   addition, more than 14 days must have passed since the device was purchased.
• No more than 2 mobile device unlocks have been complete per line of service in the last 12 months.
• T‑Mobile may request proof of purchase or additional information in its discretion and certain other exceptions may apply.