HTC — Regarding moisture in my htc desire 626g+ phone

Address:	New Delhi, Delhi, 110001
Website:	www.htc.com

Sir, i have sumitted my mobile to service centre of HTC at bareilly centre after 7 days they told me (mail) that their is a moisture problem in my mobile and i have to pay 2319/-rs for that. but my phone is still in warrenty . and they told me that your phone s out of warrenty but now i want my mobile with no. repairing and part charges.i have also told them that i will pay for the part only but they want to pay the whole i.e. labour charges, vat, taxes etc.
what can i do.
if the moisture is going in my mobile by their employees then who can i find that.