How to reset "skeletal muscle memory" ?

Hello. Sorry for bad English. I have a very important, vital question for me. I have a spasm of the short occipital muscles of the neck (the large posterior rectus muscles of the head, the superior oblique muscle of the head, the inferior oblique muscle of the head, etc.). Because of this, my biomechanics of the atlanto-occipital and atlanto-occipital joints are disturbed. As a result, the vertebral arteries are compressed and I suffer from vertebrobasilar insufficiency. Also, due to the skew of the head and c1 relative to the neck, the body creates "props" to compensate for this skew. As a result, I have a crooked spine, my back hurts, muscles all over my body are tight, my body is very heavy,
I have absolutely no strength, I can hold my hand up for a maximum of one minute. My ability to work is impaired. Chiropractors, vertebrologists greatly worsened the situation, it was a bitter difficult experience.
I would be grateful to you in life if you could advise me a drug / method that can make the brain correctly control the short occipital muscles. The fact is that they cannot be relaxed by any massage, exercises, wearing a Shants collar, and the like. Muscle relaxants don't help. Probably, when I hit the back of my head, these muscles worked like seat belts in a car, but they just can't get back to normal tone.