CAR NOT Returned

I am writing this disheartened and in disbelief. I took my car for a minor service to Renault woodmead today, and got there before 8am to have my car serviced. I left the dealership around 8:50 this morning. I waited around Woodmead retail park for some communication that my car is now ready for collection. I went back there around 1:30pm seeing that Its getting late and NO ONE from the dealership had called me, took an uber there only to find the security guard to say that they're closed and not opening on Sunday. My house keys are attached to my car keys and I left all my cards in my car!!! I need assistance in ensuring that I get some kind of a good explanation from Renault for this unimaginable NONSENSE inconvenience. Me not HAVING A CAR FOR 2 WHOLE DAYS! Being LOCKED out of my residence and NOT HAVING ANY MONEY on me to make other arrangements. What manner of ******* is this? who must compensate for this? I am beyond frustrated as we speak and I'm seeking legal assistance against the dealership.