Typically, Intercept Calls are the tri-tone message that is received from the phone company indicating a phone number is 1) not valid; 2) currently under service; 3) blocked from receiving incoming calls; or 4) all circuits are busy.
You may want to check the phone number(s) to ensure that it was entered correctly. If the phone number was entered correctly, then call the number to determine what message the phone company is indicating.