The fact that lenders who originate loans often sell or transfer the servicing rights is a fact of life these days. Even big lenders like Countrywide, Wells Fargo, Bank of America and the like occasionally sell of parts of their servicing portfolios for various reasons.
When a lender transfers the servicing of a loan, there really isn’t much you can do about it except, perhaps, refinance your loan with another lender.
If you feel very strongly about it and decide that you do not want to risk the possibility of having your new loan serviced by the lender you refer to in your question, your best bet would be to find a local bank or savings and loan. Many of them still service the loans that they make and do not sell either the servicing rights or the loans themselves.
Under Federal law, lenders are required to give you what is called a “ servicing disclosure,” which states the percentage of the loans they originated which were transferred within each of the previous three years. A look-see at that should give you an idea as to the chances of your loan being transferred in the future.
In the meantime, if you don’t want to or can’t refinance, be sure to keep a very detailed and accurate record of your dealings with your new servicer. Send correspondence by certified mail and be sure to keep copies of your mortgage statements. That way, if anything does happen, you will have proof of the facts.