This is a common problem with rubber LP lines in slide outs. The BEST way to fix is, YOU HAVE TO REPLACE THE LINE. Once it is kinked, there is no way it will stop kinking no matter how you route it. Now, when you replace the line, find a metal coil spring that will slide over the new Hose snug but not too loose. That metal spring cover will prevent the hose from kinking. IF you have room, you can install a longer replacement hose to then route it to prevent kinking when extending and retracting. MY preferred method is the Spring around the hose. Doug