Upstox is part of both depository participants, i.e. NSDL, CDSL. Your DP id may vary depending on the DP with which you have an account.
Steps to Find Upstox ID:
Your Upstox demat number has 16 digits. The DP ID will be the first 8 digits. The 8 remaining digits make up the Client ID. You can also get DP ID using your demat account number.