Problem tow ball fitting

Can't advise other than to say that I would pay a call on my local towbar fitting company unless I knew who originally fitted

+1

It could well be that as you have used it so little you have missed out some step in attaching it? You could try and google your problem? 

Try spraying the whole of the connecting parts with a silicon spray. This may help to remove it, and then respray the connecting mechanism. Ours was very stiff to attach when we first got it but fits much better after regular use.

YOU have a detachable tow ball?   

I would suggest the mechanism is dirty.  Not the bit that was carefully stored inside but the bit underneath that has filled up with salt, grit and rust through not being used.

Damned if you do - damned if you don't.

I had the same problem ( as suggested by Nagivateur )

A  small area of rust had formed on the shoulder,  which stopped the main body of the towbar from going all the way in. I had to lay on my back with a pair of goggles on to remove the rust. No more problems, just make sure the area is covered In a smearing of grease, replace the plastic cover back in when towbar removed. Then go and have a cup of tea. Remove goggles.

Some times, towbars get partially stuck & require the judicious use of a large soft face hammer to fully engage them so the locking key can be removed & the knob turns fully. It might then come off easier.

you don't say what make the towbar is. If its a witter you have to hold it up and pull rearward on the ball to engage the spring where as if its a westfalia it needs to be pushed upwards to engage the spring

Just to say that I went back to the garage I'd just purchased the car from.  Even though the tow bar etc hadn't been used a bit had broken off and was preventing the tow ball being fitted correctly or removed for a re-try.  Now waiting for a new part that the garage will fit for us and I might just ask them to pop it on.

Thank you to all for your suggestions.

Sue