Thane, MUMBAI based RERA registered under construction property was booked but later cancelled by me

Thane, MUMBAI based RERA registered under construction property was booked but later cancelled by me.REASON for cancellation- extremely poor services, discrepancy and faults done by sales and CRM team. Documents signed- ONLY RFR Form which has a clause mentioned that your booking amount stands forfeited in case of cancellation. PROOF that I have - 1.)All mails, messsages from them highlighing their faults 2.) mails in which they have apologized for their faults.3.)mail acknowledging cancellation but stating no refund will be paid 4.) Even after acknowledging cancellation, sending emails and messages demanding for further payments towards same.5.) Again on reminding cancellation, mails in which they again apologized but no reply towards refund. Doesn't the clause mentioned in the RFR form becomes void as they have done wrongful act and lots of discrepancy that too many times. This is MUMBAI,RERA registered project. Can I get refund 100 percent legally. Please guide