When you feel the caravan floor has gone spongy underfoot, this is usually delamination of the bonded floor panels.
You will find that this gets worse over time, so rectification is recommended as soon as possible.
Cutting back of floor covering is needed and in most cases can be re-laid.
As seen in photos holes need to be drilled to insert the adhesive and the holes plugged.
This is a 2-day process and easily achieved in storage or at home.