Is there a herbal formulation to open blocked fallopian tube?
There are many that can be helpful but proper diagnosis is key - see What Does Acupuncture Treat? to better understand treating patterns and not symptoms. You should consult directly with a fully trained and licensed acupuncturist.
One somewhat likely pattern (but far from the only) is described in our acupuncture for female infertility article and is what we call "Blood Stagnation with Phlegm Obstruction". After you find your correct tcm diagnosis then herbal formulas are based from this.
The formula Gui Zhi Fu Ling Wan is often used, but again only with the appropriate diagnosis.
Blocked fellopian tubes
Blocked fallopian tubes are often due to an unresolved infection, which is sometimes viewed as damp heat in TCM. Sometimes using a formula that addresses Damp Heat is helpful to clearing this. I like formulas with Huang Bai in them as Huang Bai is great for Damp Heat in the lower jiao. I would add this to a formula that is indicated for your constitution.