50451: Only one identifier allowed for lookup: use either Identity or Address

This error occurs when your lookup request includes both Identity and Address. The participant conversation lookup supports exactly one of these parameters at a time.

• Your request included both Identity and Address for the same lookup.
• Your request mixed a Chat user identifier with a non-Chat participant address in one query. Chat users are identified by identity, while non-Chat participants are looked up by address.

• Send only Identity when you look up conversations for a Chat user.
• Send only Address when you look up conversations for a non-Chat participant, such as an SMS or WhatsApp address.
• If you use Address, URL-encode the value before you send the request. For phone numbers, encode + as %2B.

• Participant Conversation Resource
• Twilio Conversations Overview
• User Identity and Access Tokens for Conversations