Sorry to hear about your clutch problems and as stated above the garage who carried out the work should rectify this problem FOC if they diagnosed the problem and carried out the repairs.
Can you give us a few details about the problem and the reason for having the clutch replaced.
Such as: Did you have a complete clutch kit fitted or just a friction plate? Was the original clutch slipping or juddery?
Did you have a gear selection problem previously and the clutch was diagnosed as being the cause?
Can you select gears OK with the engine not running?
Sorry for the interrogation but the more info we have the more likely that we will be able to offer possible solutions.