Hello, dr.al-hebshi and welcome to our Support Community!
Two years is a long time to go without being able to access the full features of your My T-Mobile account. You mentioned that you've worked with customer service in the past on this -- have they filed a helpdesk ticket for you yet? If not, that's the next step that needs to be taken. A helpdesk ticket can be filed by dialing 611 or working with T-Force via Facebook/Twitter.
Do you have more than one line? If so someone already made their line the primary. You need to have the rep reset it and then you go in and make yours the primary.