It can be yust the tire-pressure , but can also be because of the weight division that is to much to the back.
Then it lifts up the front, wich chanches the alignment and the springs are at their end.
Can also be that its the other way around for RV.s with a longer wheelbase. Then the springs are yust to soft, and hang to the end of the silent-blocks ( if its the right word for the rubber at the end of the springway to prefent the wheelarm from touching metal).
Then other springs is the solution.
But also doing some weight shifting to the front can salve the problem then.
If you look under the car , you can see for yourselfes if the springs are at the end and wich end.
But first look at the needed tire pressure , its the cheapest way to salve it and mayby enaugh.