We need more to go on to be of better help..........runny poo can happen for many reasons.
How is she otherwise? Energy level? How is her appetite? Any discharges from eyes or nose?
What is her diet? Has it changed recently?Does she get any outdoor time to eat outdoor stuff (bugs, plants)?
Has she ever been wormed?
Is all poo runny or just intermittently?
How long have you had her? Do you have others? How are they?
Etc..........
JJ