clutch problems

Hey all, just a question here…I just recently(about a month ago) got my clutch, clutch master, and slave cylinder replaced because the clutch was completely dead along with the other parts, but even with my new clutch, after the engine heats up a little bit the clutch will start to slip. Its getting especially bad now that its nearing summer and the car is usually pretty hot by the time i get in. The flywheel was machined and all so i really dont see what the problem could be. Any suggestions would be great thanks!