Did you get the NJ property tax deduction instead? 

Or, perhaps your income did not qualify. Your gross income must be more than $20,000 ($10,000 if filing status is single or married/CU partner, filing separate return), OR  you (and/ or your spouse/civil union partner if filing jointly) were 65 or older or blind or disabled on the last day of the tax year.

https://www.state.nj.us/treasury/taxation/proptaxdeduc_credit.shtml

Aater posting the query I leawrned that the  $50 credit will not be refunded separately, but will be included in my Homestead Rebate.

Thank you for your reply.