Judy, if the change in freezer performance is related to the switch from propane to electric, you may have a problem with the electric heating element.
But with RV Gas/Electric refrigerators, the cooling unit usually cools the freezer area first, and then the refrigerator area. So it's unusual to have a situation where the freezer doesn't cool well, but the refrigerator does. Also, the refrigerator doors usually get opened more frequently than the freezer doors.
You may have an air leak with the freezer door(s). One clue that might confirm this would be an unusually frost buildup in the freezer. Something may be holding the door open slightly, or one of the seals might have come loose.