First of all, you signed an agreement with a fixed rate, and just because it was sold does not mean they have the right to change the mortgage agreement. If you signed a new mortgage agreement stating the new agreement then you are liable for that, but you can call your mortgage company and tell them you have a copy of the agreement you signed and, that you didn't agree to an arm. To sum it up, unless you re-signed a mortgage agreement, they DO NOT have the right to change anything just because they have baught your mortgage from your original mortgagor. Please do not let them run you over. Good luck.