Withdrawing from LLM LPC Course

Hii,
I'm considering to withdrawing from the BPP LLM LPC course as, I was due to start mid Jan but have only just started week 2 (on the 6th of march), the course itself has also not been what I thought it would be so I am considering withdrawing.

I have not yet paid my first installment (due to their delay in registering me) and also because they have only just sent the payment plan on the 6th of March (on my request).

Would I be liable to pay the whole 15k? Or just the first installment of 5k??