I have a 6 month old cocker who is generally obedient but the moment I get him to go in the car boot where his cage is he simply lies on the ground like a limp noodle and won't get up and eventually rolls under the damn car. He never used to do this its a fairly recent thing I understand he wants playing with but at the moment its bad people look at me like I beat my dog which I don't. He does it for all family members too. I have tried walking him to the car on a lead but same thing just lies down like a wet fish. Ideas?