Agree with Doggy Daddy. Have them fix it. This should not have happened. MH manufacturers use special thin set and grout to flex a bit with the coach frame. They must have used the wrong stuff or did not wait long enough for the grout to cure before moving the floor.
If you want to take this opportunity to have them install some other product, they may charge you for it.
Bob & Joan Alexander, 2010 Tiffin Phaeton 36 QSH, 2013 Jeep Wrangler (toad)
Lobo & Juniper (woof, woof)