Lance travel trailer slide out stops half way

Have you lubed the mechanism recently? Are the batteries fully charged when this happens? Load check the batteries.

Camper was plugged into electrical power each time, so the voltage should have been good but I will have the batteries checked out, slide out manual says it is designed to be maintenance free except for the preservative treatment for the seals.

For what it's worth with my previous TT's and 5er (as well as our motorhome) we've always been told to keep the trailer plugged in to the truck with the engine running when extending or retracting the slides. I could notice the difference in how well the slides performed when I did that.

Class c bedroom slide did the same thing. The slides were dirty and the strain on the motor shut off the motor on the internal protector.
I would have to pull off the mattress and undo the plywood platform.
Cleaned and lubed the slides and it worked well. I used a dry lube.
Anything oily will only attract more dirt. I found an access hole for wiring was not sealed properly, it allowed dust to come in. As We desert camp and dirt roads are common it was a problem.
The salesman said the slides were maintenance free, :h with a straight face?