Do you have the receipt for the deposit of the token amount?
Actually it is an illegal practice to obtain token amount without executing an agreement for sale.
A copy of the agreement for sale has to be furnished to the prospective buyer, if he is willing to accept the terms and conditions then he can pay the initial amount and get the agreement registered in his favor.
This is the actual procedure.
Now do you have evidence for the payment of this amount.
You issue a legal notice to the builder to return the amount based on the evidence for having deposited the token amount with the builder, if he is not returning or not replying or responding, drag him to consumer court for recovery and compensation or file a civil suit for recovery of money.
Consult a local advocate and proceed further.