T - Mobile Migration fees Internet

I recently switched from an old family plan to to T-Mobiles even more plus plans.

The Representative explained to me that there would be a $35.00 migration fee after discussing my current plan details including the fact that I had 2 lines. I assumed that the would be exactly would the agent said it would be given the fact that he was familiar with my account and new that there were 2 lines on it.  But of course when the bill came in the migration fee was charged twice, one for each line. 
I feel that I was mislead by the agent who never told me the real cost of switching to the new plan would be $70 not the $35.00 he quoted.

I called T-Mobile express my concerns and the representative just kept repeating that the migration fee was a per line fee.  If they had been straight with me in the first place I could have made a more informed decision.