Help needed with halfords

Hi all, I have purchased a dab radio from halfords.
Before I purchased I asked for advice over the phone as to whether the radio I had chosen would fit the car (reg given) and if I needed to purchase anything else, I was told that I would need a cable if I want the steering wheel controller to work. I said we don't use them so that is ok I was also told I would need a dab aerial.

When I went into store I asked the same question, and was given the same answer.

So I purchased the two items and booked an appointment for wefit service.
Two weeks later on appointment day we (myself, wife and four kids) turned up, the fitter took one look and said you need a cable and a facia.
To my surprise I said I was not told this when I asked and I was told that I do.

So I purchased those and booked in again for another week.

On the next appointment we went for fitting and was told the wrong facia has arrived but they fitted anyway and reordered the facia. I was in the Carpark for 3 and half hours for a one hour appointment because they had difficulty and now have received a £60 fine from the Carpark.
At this point the built-in satnav stops working.

I have been back another time to have the facia fitted and to inspect the satnav.

The facia was fitted but the satnav does not work.

I was then promised £15 compensation that has not yet been given. And was told the store manager will ring me the next day with what needs to be done and about the parking charge, this phone call never happened.

I have just had to chase this up and they want me to go into store this Sunday for another inspection.

What should I expect or request them to do?

Sorry for the essay

Thank you