Sorry to hear this at least they took the car & left everything else alone.
This is pretty much how motability left me when my MG broke down. Europcar don’t have any suitable cars & can’t deliver one to you even if they did. National problem lack of hire cars (funny I called 2 other companies who could deliver an automatic same day).
When I did get one bits of it were broken too. Anyway what I ended up dou g was fill in the complaint form online & that team will get back to you.
In your situation before doing that id call them back explain the situation & just ask them what are you going to do to help me (in the nicest possible way) if you get fobbed off again go fill in the complaint form & start that ball rolling.
I don’t have much experience the first time I called motability for help they really let me down but others have fared better best bet is to call them & just ask the question. What they offered me for a breakdown was:
1. Payments for not having a car, paid after you get the car back
2. A taxi account, no good for rural types as I needed to go 6 miles & they sent a taxi from nearest city 30 miles away so 6 mile trip cost £52
3. Try to get a suitable hire car asap
Theyre there to help so they should sort it.
Good luck