Pain can manifest in the body even after the physical healing process is complete due to a variety of factors.

One possible reason is that the nervous system may still be sensitized, even after the injury or illness has healed. This means that the nerves may still be transmitting pain signals to the brain even though there is no longer any physical damage.

Another possible reason is that the brain may have become accustomed to the sensation of pain during the healing process, and continues to generate pain signals even though there is no longer any actual tissue damage.

Psychological factors such as stress, anxiety, and depression can also contribute to the experience of pain. These emotions can cause changes in the body’s stress response system, which can increase pain sensitivity.

In some cases, pain may also be the result of a chronic condition, such as fibromyalgia or chronic fatigue syndrome, which can cause ongoing pain even after the original injury or illness has healed.
Hypnosis has been shown to be an effective method for managing pain in some people, and there are a few ways in which it may work to switch off pain:
 
Changing perception of pain: During hypnosis, a person is guided to focus their attention on something other than the pain. This can help to change their perception of the pain and make it less intense or overwhelming.

Altering pain signals: Hypnosis can also work by altering the way the brain processes pain signals. Hypnosis can change the way the brain processes pain signals, making them less intense or easier to tolerate.
 
Relaxation: Hypnosis often involves deep relaxation, which can help to reduce muscle tension and promote a sense of calm. This can help to reduce pain that is related to tension or stress.
 
Increasing suggestibility: During hypnosis, a person may be more open to suggestion, which can be used to suggest that they will feel less pain or that the pain will be more manageable. This can help to shift the person’s mindset and make the pain easier to cope with.