You definitely need to defrost both the freezer and get rid of the ice buildup on the fins in the refrigerator immediately, like tonight. (I have to do mine about every 3-4 months.) There should be only a small amount of ice on the fins and in the back of the freezer!!
First, you need to determine if you have that drain tray under the fins and if the hole at one end is not clogged. It should sit so that the drain hole fits into a little fitting that enables the water to drain out the back of the refrigerator and through a hose of some sort that lets the water go outside. You will need to take the outside cover out to determine this. If you don't have a drain tray, you are going to need a stack of rags to sop up the melted water.
Second, while you have the outside cover off, make sure there are not any insect nests anywhere. Sometimes wasps or other bugs decide this is a handy place to set up housekeeping and take a long trip at the same time. They can clog up the drain system and also cause electrical problems.
Third, assuming there is nothing blocking water from draining when you defrost your refrigerator and you have removed any insect nests, go back inside and turn off the refrigerator by pushing the Off button in the control panel.
Fourth, empty everything out of your refrigerator. (I get away by just emptying the top shelf if I know the drain is working properly.)
Fifth, get out a hair dryer and wave it back and forth over the fins until the ice melts. Don't let it stay in one spot long enough to melt any plastic--just keep it moving. The melted water will be caught by the little tray and exit down the hole and run outside down the side of your RV, assuming everything is clear. Keep at it until the ice on the fins is completely melted.
Finally, wipe any water up that dripped on your floor or got into the bottom of your refrigerator. You might want to remove the bottom vegetable drawers to check on this. Good time to wipe shelves off and toss any spoiled food, as well!!! This usually takes me 15-20 minutes.
All of this will wear you out, but you need to tackle the freezer next. I completely empty it out of all food and do the hair dryer thing on the back wall, but again, make sure you do not melt any plastic, so keep it moving and watch what you are doing.
Unfortunately, on my freezer there is no hole to drain melted water, so I have to sop it up with rags and then wring them in the sink. When all the ice is gone, wipe everything down, and again toss out food you no longer want and did not know you had!!
Have fun!!! Note that it will take a few hours to get completely cold again, so you may need to put some food in a cooler for a while. But once you know the problem is NOT an ice buildup, you can tackle other potential causes.