Sirus/XM Radio Lifetime Subscriptions Internet

I have two lifetime subscriptions to Sirius (now Sirius/xm) radio.  In Oct. of 2010 I purchased a 2010 Toyota Prius which came with an XM radio and a trial 90 day subscription.  It seems that one type of radio will not pick signals from the other .... i.e. - a sirus radio can not pick up xm signal and vis-a-versa, after 90 days my xm radio was turned off in my prius.  I have  called Sirius/XM and sent countless emails trying to get credit for one of my Sirius lifetime subscriptions for an XM subscription.  Since they have merged it seems to me that a switch should not be that difficult. All calls to call center go to a forgein country.  All i want is to convert one of my lifetime subscriptions to Sirus to a subscription of XM... all they, Sirus/XM has to do is turn my radio back on and assign me an account with the XM side of Sirus/XM.