My daughter has been having very runny poop for like a month off and on what should I do!?

See your physician. Watery stool for a month needs an evaluation by a physician expert in the care of children.
Stool Kit. For loose stools for over 4 weeks i suggest a history and physical by primary care physician and stool kit to test for infections and parasites.
Age? other? Hard to know without more specifics, age, travel, family history of bowel problems, nocturnal (middle of the night) stools, accidents, bleeding, weight loss, etc. A full exam and history should narrow down the list. Infections (parasites) can be tested for. Antidiarrheals can be very useful once infection is excluded. But if there is an underlying cause, this needs to be treated.