Paramount Group — non payment of pre emi interest and possession o[censored]nits

I have bought 2 studio apartments in paramount golf foreste o-619a and o-620.
I am paying emi since march 2018 and nothing have been received against pre emi interest as committed and no information about the possession.
Let me know when will i receive my pre emi interest? Or should i go legal?
I have called several times but always received same response that your pre emi will process soon.
Is there any policy or tat to resolve customer complaint. Please behave professionally.