Leaperd Mollie Nipping Other Fish

[Taiidan]

i got 3 leaperd mollies 1male and 2females about 4h ago and in the last 1hr 1 of the femals seems to like to nip my swordtails tail (female) and im not happy with it has any of you out there had the same trubble

but at the end of the day i think its 1 of my weakest fish