I have just picked my car up from garage after 6 bearings and end plate changed on my Astra Sri turbo gearbox, now my clutch is slipping badly and I have an oil leak that wasn't there before
Return the car to the garage that did the work, complain that they have not completed the work to a satisfactory manor, and actually created further issues. And that you'd like it repaired correctly.
If it's a decent shop they should repair the car for you without question. However If not and they deny all knowledge etc, then you are going to have to get a good mechanic to inspect the vehicle, give you details of the shoddy work done, and what it will cost for repair. And then if necessary sue the first garage for the cost of the repairs required because of their mistakes.