I have wrote a program with more tasks. I use 6 sensors in the robot, and I noticed that when I try to use all of them in different tasks, they don't operate well. So, is it possible that I can't use so much sensors at the same time, or I did something wrong? What should I do? I tried to write waits among the tasks but it didn't help. (I use some distributors, too. I don't know, it may also can cause the problem). Thank you in advance.

Generally you don't need multitasking. The most likely did something wrong. You can certainly use six sensors, but trying to coordinate six tasks all checking stuff at the same time is difficult. It'd be helpful if you could post your current code and what'd your goal is.

If you're reading/monitoring all of the sensors, just put it in one task and read from all of them once per loop.