Advice needed ASAP regarding car purchase

Hi guys not sure if I’ve posted this in the correct forum but I’m after some advice.

I brought a second hand Peugeot 207 in January as my first car, when I brought it of the dealer I was given a 3 month warranty.
2 weeks before this warranty expired the car wouldn’t start so I took it to them and it turned out to be a faulty ECU they kept the car and replaced the ECU under warranty however this took them 2 and a half weeks once they finished the repair they told me I had a life time warranty on this part.

Today 5 weeks later the car won’t start and has the exact same symptoms as last time I’ve have spoken to the garage who have said they can’t look at it for another week due to a refurb and they are not prepared to let me have it corrected by another garage and them pay the charges or even offer me a courtesy car. They have been no help what so ever. So now Im paying for two taxis a day just to get to and from work and they haven’t even had the car yet so it’s going to be around 3 weeks before I have a working car again. Do I have any rights regarding this? As I’m going to be massively out of pocket for the next few weeks. Can I request a refund on the car due to not owning it for 6 months?

Thanks I’m advance