untyed welcome to irv2.
With your slide in get on floor with flashlite and take a look at the roller on that end.
The roller maybe cracked or off the pin mounting bracket.
If it is you will have to fix with new one or remount braket. You will have to lift slide with bar and block up to get room to work
. Move the slide out and stop so its not closed in recess of side wall.
If you have a good dealer maybe they can help.
Is your floor a rug or tile where roller rests on floor.