Tsh is varying every month. Doctor is changing the dosages but not stabilizing. Wat is reason. I have hashimoto's.

Depends upon. What you mean by "varying". Tsh is not constant. Make sure you're on brand name replacement. Hashimoto's can cause variable thyroid test results by itself. You also need to wait a full six weeks after a dose change to let it equilibrate and levels to stabilize. See an endocrinologist if necessary.