I suspect that I am being controlled by high-tech surveillance means. The other party knows everything I see, think, and do. Only I can hear the other party’s voice.

There are two possibilities. One is that someone is really monitoring your brain, and the other is that you may be overly fantasizing. But it is very difficult for you to judge, because whether it is monitoring or symptoms, they are just feelings reflected in your body. You must find a kind of substantial, objective, external physical evidence to help you judge what is happening. In any case, witness testimony is unreliable unless it is a professional psychiatrist. But since your situation is relatively rare, I personally recommend that it is more reliable to find physical evidence. Determine the situation and proceed further.