If you are represented by an attorney, you need to make an appointment with him or her and discuss this situation. If you are not represented, you should be. If you are at the stage of the proceedings where there is a divorce master involved, it will be extremely difficult for you to represent yourself and you will almost certainly have a worse result without representation.
Frankly, I have difficulty believing that the divorce master knowingly lied. The divorce masters I know in Lebanon county are good, hard-working attorneys. If the master filed a motion and you disagreed with the facts asserted, you should have gone to a hearing on the matter. Again, this is something your attorney can explain better.
You may want to check with either Mid Penn Legal Services or the Lebanon County Bar Association to get a referral. Both should be in the Lebanon phone book.