Problem with careco and mobility scooter

I bought a mobility scooter from careco on the 14th February told them it needed to be lightweight to be stored in boot of car.purchased a li tech neon for £2000 put it together when it arrived a few days later and went out on it was chuffed.
I loaded it into car as I had been shown and motor moved about scratching chassis!
I wasn’t happy and complained and was told I should have put a clolth on it by showroom!
went to the complaint department and was told as it was only 16 days old I could have a credit note minus deduction for damages!
long story short I decided to live with scratches as mobility scooter worked fine or so I thought.
Then I had to take my daughter to hospital yesterday and got mobility scooter out of car and after a few minutes of driving it the motor started making a clunking sound and cut out!
The hospital trip was a nightmare as my daughter had to push me and scooter!
Rang the showroom of careco and was told to take it in which I did.
manager at store was very rude and accused me of damaging scooter I said it was obviously a manufacturer fault and was entitled to a refund she said she would send an engineer to my address in next few weeks and if I was liable I’d have to pay!
phoned citizens advice and scope and was told to put it in writing.
at a complete loss can’t sleep for worrying 
anybody else had problems with careco?